QByteArray Class Reference |
Format | Meaning |
---|---|
e | format as [-]9.9e[+|-]999 |
E | format as [-]9.9E[+|-]999 |
f | format as [-]9.9 |
g | use e or f format, whichever is the most concise |
G | use E or f format, whichever is the most concise |
With 'e', 'E', and 'f', prec is the number of digits after the decimal point. With 'g' and 'G', prec is the maximum number of significant digits (trailing zeroes are omitted).
QByteArray ba = QByteArray::number(12.3456, 'E', 3);
// ba == 1.235E+01
Note: The format of the number is not localized; the default C locale is used irrespective of the user's locale.
See also toDouble().
Prepends the byte array ba to this byte array and returns a reference to this byte array.
Example:
QByteArray x("ship");
QByteArray y("air");
x.prepend(y);
// x == "airship"
This is the same as insert(0, ba).
Note: QByteArray is an implicitly shared class. Consequently, if this is an empty QByteArray, then this will just share the data held in ba. In this case, no copying of data is done.
See also append() and insert().
This is an overloaded member function, provided for convenience.
Prepends the string str to this byte array.
This is an overloaded member function, provided for convenience.
Prepends the character ch to this byte array.
This function is provided for STL compatibility. It is equivalent to append(other).
This is an overloaded member function, provided for convenience.
Same as append(str).
This is an overloaded member function, provided for convenience.
Same as append(ch).
This function is provided for STL compatibility. It is equivalent to prepend(other).
This is an overloaded member function, provided for convenience.
Same as prepend(str).
This is an overloaded member function, provided for convenience.
Same as prepend(ch).
Removes len bytes from the array, starting at index position pos, and returns a reference to the array.
If pos is out of range, nothing happens. If pos is valid, but pos + len is larger than the size of the array, the array is truncated at position pos.
Example:
QByteArray ba("Montreal");
ba.remove(1, 4);
// ba == "Meal"
See also insert() and replace().
Replaces len bytes from index position pos with the byte array after, and returns a reference to this byte array.
Example:
QByteArray x("Say yes!");
QByteArray y("no");
x.replace(4, 3, y);
// x == "Say no!"
See also insert() and remove().
This is an overloaded member function, provided for convenience.
This is an overloaded member function, provided for convenience.
Replaces every occurrence of the byte array before with the byte array after.
Example:
QByteArray ba("colour behaviour flavour neighbour");
ba.replace(QByteArray("ou"), QByteArray("o"));
// ba == "color behavior flavor neighbor"
This is an overloaded member function, provided for convenience.
Replaces every occurrence of the string before with the byte array after.
This is an overloaded member function, provided for convenience.
Replaces every occurrence of the byte array before with the string after.
This is an overloaded member function, provided for convenience.
Replaces every occurrence of the string before with the byte array after. The Unicode data is converted into 8-bit characters using QString::toAscii().
If the QString contains non-ASCII Unicode characters, using this function can lead to loss of information. You can disable this function by defining QT_NO_CAST_TO_ASCII when you compile your applications. You then need to call QString::toAscii() (or QString::toLatin1() or QString::toUtf8() or QString::toLocal8Bit()) explicitly if you want to convert the data to const char *.
This is an overloaded member function, provided for convenience.
Replaces every occurrence of the string before with the string after.
This is an overloaded member function, provided for convenience.
Replaces every occurrence of the string before with the string after.
This is an overloaded member function, provided for convenience.
Replaces every occurrence of the character before with the byte array after.
This is an overloaded member function, provided for convenience.
Replaces every occurrence of the character before with the string after. The Unicode data is converted into 8-bit characters using QString::toAscii().
If the QString contains non-ASCII Unicode characters, using this function can lead to loss of information. You can disable this function by defining QT_NO_CAST_TO_ASCII when you compile your applications. You then need to call QString::toAscii() (or QString::toLatin1() or QString::toUtf8() or QString::toLocal8Bit()) explicitly if you want to convert the data to const char *.
This is an overloaded member function, provided for convenience.
Replaces every occurrence of the character before with the string after.
This is an overloaded member function, provided for convenience.
Replaces every occurrence of the character before with the character after.
Attempts to allocate memory for at least size bytes. If you know in advance how large the byte array will be, you can call this function, and if you call resize() often you are likely to get better performance. If size is an underestimate, the worst that will happen is that the QByteArray will be a bit slower.
The sole purpose of this function is to provide a means of fine tuning QByteArray's memory usage. In general, you will rarely ever need to call this function. If you want to change the size of the byte array, call resize().
See also squeeze() and capacity().
Sets the size of the byte array to size bytes.
If size is greater than the current size, the byte array is extended to make it size bytes with the extra bytes added to the end. The new bytes are uninitialized.
If size is less than the current size, bytes are removed from the end.
See also size().
Returns a byte array that contains the rightmost len bytes of this byte array.
The entire byte array is returned if len is greater than size().
Example:
QByteArray x("Pineapple");
QByteArray y = x.right(5);
// y == "apple"
See also endsWith(), left(), and mid().
Returns a byte array of size width that contains the fill character followed by this byte array.
If truncate is false and the size of the byte array is more than width, then the returned byte array is a copy of this byte array.
If truncate is true and the size of the byte array is more than width, then the resulting byte array is truncated at position width.
Example:
QByteArray x("apple");
QByteArray y = x.rightJustified(8, '.'); // y == "...apple"
See also leftJustified().
Sets the byte array to the printed value of n in base base (10 by default) and returns a reference to the byte array. The base can be any value between 2 and 36.
Example:
QByteArray ba; int n = 63; ba.setNum(n); // ba == "63" ba.setNum(n, 16); // ba == "3f"
Note: The format of the number is not localized; the default C locale is used irrespective of the user's locale.
See also number() and toInt().
This is an overloaded member function, provided for convenience.
See also toUInt().
This is an overloaded member function, provided for convenience.
See also toShort().
This is an overloaded member function, provided for convenience.
See also toUShort().
This is an overloaded member function, provided for convenience.
See also toLongLong().
This is an overloaded member function, provided for convenience.
See also toULongLong().
This is an overloaded member function, provided for convenience.
Sets the byte array to the printed value of n, formatted in format f with precision prec, and returns a reference to the byte array.
The format f can be any of the following:
Format | Meaning |
---|---|
e | format as [-]9.9e[+|-]999 |
E | format as [-]9.9E[+|-]999 |
f | format as [-]9.9 |
g | use e or f format, whichever is the most concise |
G | use E or f format, whichever is the most concise |
With 'e', 'E', and 'f', prec is the number of digits after the decimal point. With 'g' and 'G', prec is the maximum number of significant digits (trailing zeroes are omitted).
Note: The format of the number is not localized; the default C locale is used irrespective of the user's locale.
See also toDouble().
This is an overloaded member function, provided for convenience.
Sets the byte array to the printed value of n, formatted in format f with precision prec, and returns a reference to the byte array.
Note: The format of the number is not localized; the default C locale is used irrespective of the user's locale.
See also toFloat().
Returns a byte array that has whitespace removed from the start and the end, and which has each sequence of internal whitespace replaced with a single space.
Whitespace means any character for which the standard C++ isspace() function returns true. This includes the ASCII characters '\t', '\n', '\v', '\f', '\r', and ' '.
Example:
QByteArray ba(" lots\t of\nwhitespace\r\n ");
ba = ba.simplified();
// ba == "lots of whitespace";
See also trimmed().
Returns the number of bytes in this byte array.
The last byte in the byte array is at position size() - 1. In addition, QByteArray ensures that the byte at position size() is always '\0', so that you can use the return value of data() and constData() as arguments to functions that expect '\0'-terminated strings.
Example:
QByteArray ba("Hello"); int n = ba.size(); // n == 5 ba.data()[0]; // returns 'H' ba.data()[4]; // returns 'o' ba.data()[5]; // returns '\0'
See also isEmpty() and resize().
Splits the byte array into subarrays wherever sep occurs, and returns the list of those arrays. If sep does not match anywhere in the byte array, split() returns a single-element list containing this byte array.
Releases any memory not required to store the array's data.
The sole purpose of this function is to provide a means of fine tuning QByteArray's memory usage. In general, you will rarely ever need to call this function.
See also reserve() and capacity().
Returns true if this byte array starts with byte array ba; otherwise returns false.
Example:
QByteArray url("ftp://ftp.trolltech.com/");
if (url.startsWith("ftp:"))
...
See also endsWith() and left().
This is an overloaded member function, provided for convenience.
Returns true if this byte array starts with string str; otherwise returns false.
This is an overloaded member function, provided for convenience.
Returns true if this byte array starts with character ch; otherwise returns false.
Returns a copy of the byte array, encoded as Base64.
QByteArray text("Qt is great!");
text.toBase64(); // returns "UXQgaXMgZ3JlYXQh"
The algorithm used to encode Base64-encoded data is defined in RFC 2045.
See also fromBase64().
Returns the byte array converted to a double value.
Returns 0.0 if the conversion fails.
If ok is not 0: if a conversion error occurs, *ok is set to false; otherwise *ok is set to true.
QByteArray string("1234.56");
double a = string.toDouble(); // a == 1234.56
Note: The conversion of the number is performed in the default C locale, irrespective of the user's locale.
See also number().
Returns the byte array converted to a float value.
Returns 0.0 if the conversion fails.
If ok is not 0: if a conversion error occurs, *ok is set to false; otherwise *ok is set to true.
Note: The conversion of the number is performed in the default C locale, irrespective of the user's locale.
See also number().
Returns a hex encoded copy of the byte array. The hex encoding uses the numbers 0-9 and the letters a-f.
See also fromHex().
Returns the byte array converted to an int using base base, which is 10 by default and must be between 2 and 36, or 0.
If base is 0, the base is determined automatically using the following rules: If the byte array begins with "0x", it is assumed to be hexadecimal; if it begins with "0", it is assumed to be octal; otherwise it is assumed to be decimal.
Returns 0 if the conversion fails.
If ok is not 0: if a conversion error occurs, *ok is set to false; otherwise *ok is set to true.
QByteArray str("FF"); bool ok; int hex = str.toInt(&ok, 16); // hex == 255, ok == true int dec = str.toInt(&ok, 10); // dec == 0, ok == false
Note: The conversion of the number is performed in the default C locale, irrespective of the user's locale.
See also number().
Returns the byte array converted to a long int using base base, which is 10 by default and must be between 2 and 36, or 0.
If base is 0, the base is determined automatically using the following rules: If the byte array begins with "0x", it is assumed to be hexadecimal; if it begins with "0", it is assumed to be octal; otherwise it is assumed to be decimal.
Returns 0 if the conversion fails.
If ok is not 0: if a conversion error occurs, *ok is set to false; otherwise *ok is set to true.
QByteArray str("FF"); bool ok; long hex = str.toLong(&ok, 16); // hex == 255, ok == true long dec = str.toLong(&ok, 10); // dec == 0, ok == false
Note: The conversion of the number is performed in the default C locale, irrespective of the user's locale.
This function was introduced in Qt 4.1.
See also number().
Returns the byte array converted to a long long using base base, which is 10 by default and must be between 2 and 36, or 0.
If base is 0, the base is determined automatically using the following rules: If the byte array begins with "0x", it is assumed to be hexadecimal; if it begins with "0", it is assumed to be octal; otherwise it is assumed to be decimal.
Returns 0 if the conversion fails.
If ok is not 0: if a conversion error occurs, *ok is set to false; otherwise *ok is set to true.
Note: The conversion of the number is performed in the default C locale, irrespective of the user's locale.
See also number().
Returns a lowercase copy of the byte array. The bytearray is interpreted as a Latin-1 encoded string.
Example:
QByteArray x("TROlltECH");
QByteArray y = x.toLower();
// y == "trolltech"
See also toUpper() and 8-bit Character Comparisons.
Returns a URI/URL-style percent-encoded copy of this byte array. The percent parameter allows you to override the default '%' character for another.
By default, this function will encode all characters that are not one of the following:
ALPHA ("a" to "z" and "A" to "Z") / DIGIT (0 to 9) / "-" / "." / "_" / "~"
To prevent characters from being encoded pass them to exclude. To force characters to be encoded pass them to include. The percent character is always encoded.
Example:
QByteArray text = "{a fishy string?}";
QByteArray ba = text.toPercentEncoding("{}", "s");
qDebug(ba.constData());
// prints "{a fi%73hy %73tring%3F}"
The hex encoding uses the numbers 0-9 and the uppercase letters A-F.
This function was introduced in Qt 4.4.
See also fromPercentEncoding() and QUrl::toPercentEncoding().
Returns the byte array converted to a short using base base, which is 10 by default and must be between 2 and 36, or 0.
If base is 0, the base is determined automatically using the following rules: If the byte array begins with "0x", it is assumed to be hexadecimal; if it begins with "0", it is assumed to be octal; otherwise it is assumed to be decimal.
Returns 0 if the conversion fails.
If ok is not 0: if a conversion error occurs, *ok is set to false; otherwise *ok is set to true.
Note: The conversion of the number is performed in the default C locale, irrespective of the user's locale.
See also number().
Returns the byte array converted to an unsigned int using base base, which is 10 by default and must be between 2 and 36, or 0.
If base is 0, the base is determined automatically using the following rules: If the byte array begins with "0x", it is assumed to be hexadecimal; if it begins with "0", it is assumed to be octal; otherwise it is assumed to be decimal.
Returns 0 if the conversion fails.
If ok is not 0: if a conversion error occurs, *ok is set to false; otherwise *ok is set to true.
Note: The conversion of the number is performed in the default C locale, irrespective of the user's locale.
See also number().
Returns the byte array converted to an unsigned long int using base base, which is 10 by default and must be between 2 and 36, or 0.
If base is 0, the base is determined automatically using the following rules: If the byte array begins with "0x", it is assumed to be hexadecimal; if it begins with "0", it is assumed to be octal; otherwise it is assumed to be decimal.
Returns 0 if the conversion fails.
If ok is not 0: if a conversion error occurs, *ok is set to false; otherwise *ok is set to true.
Note: The conversion of the number is performed in the default C locale, irrespective of the user's locale.
This function was introduced in Qt 4.1.
See also number().
Returns the byte array converted to an unsigned long long using base base, which is 10 by default and must be between 2 and 36, or 0.
If base is 0, the base is determined automatically using the following rules: If the byte array begins with "0x", it is assumed to be hexadecimal; if it begins with "0", it is assumed to be octal; otherwise it is assumed to be decimal.
Returns 0 if the conversion fails.
If ok is not 0: if a conversion error occurs, *ok is set to false; otherwise *ok is set to true.
Note: The conversion of the number is performed in the default C locale, irrespective of the user's locale.
See also number().
Returns the byte array converted to an unsigned short using base base, which is 10 by default and must be between 2 and 36, or 0.
If base is 0, the base is determined automatically using the following rules: If the byte array begins with "0x", it is assumed to be hexadecimal; if it begins with "0", it is assumed to be octal; otherwise it is assumed to be decimal.
Returns 0 if the conversion fails.
If ok is not 0: if a conversion error occurs, *ok is set to false; otherwise *ok is set to true.
Note: The conversion of the number is performed in the default C locale, irrespective of the user's locale.
See also number().
Returns an uppercase copy of the byte array. The bytearray is interpreted as a Latin-1 encoded string.
Example:
QByteArray x("TROlltECH");
QByteArray y = x.toUpper();
// y == "TROLLTECH"
See also toLower() and 8-bit Character Comparisons.
Returns a byte array that has whitespace removed from the start and the end.
Whitespace means any character for which the standard C++ isspace() function returns true. This includes the ASCII characters '\t', '\n', '\v', '\f', '\r', and ' '.
Example:
QByteArray ba(" lots\t of\nwhitespace\r\n ");
ba = ba.trimmed();
// ba == "lots\t of\nwhitespace";
Unlike simplified(), trimmed() leaves internal whitespace alone.
See also simplified().
Truncates the byte array at index position pos.
If pos is beyond the end of the array, nothing happens.
Example:
QByteArray ba("Stockholm");
ba.truncate(5); // ba == "Stock"
See also chop(), resize(), and left().
Returns a pointer to the data stored in the byte array. The pointer can be used to access the bytes that compose the array. The data is '\0'-terminated. The pointer remains valid as long as the array isn't reallocated or destroyed.
This operator is mostly useful to pass a byte array to a function that accepts a const char *.
Note: A QByteArray can store any byte values including '\0's, but most functions that take char * arguments assume that the data ends at the first '\0' they encounter.
See also constData().
Returns a void pointer to the data.
This operator is mostly useful to pass a byte array to a function that accepts a void *.
See also constData().
Returns true if this byte array is not equal to string str; otherwise returns false.
The Unicode data is converted into 8-bit characters using QString::toAscii().
The comparison is case sensitive.
You can disable this operator by defining QT_NO_CAST_FROM_ASCII when you compile your applications. You then need to call QString::fromAscii(), QString::fromLatin1(), QString::fromUtf8(), or QString::fromLocal8Bit() explicitly if you want to convert the byte array to a QString before doing the comparison.
Appends the byte array ba onto the end of this byte array and returns a reference to this byte array.
Example:
QByteArray x("free");
QByteArray y("dom");
x += y;
// x == "freedom"
This operation is typically very fast (constant time), because QByteArray preallocates extra space at the end of the character data so it can grow without reallocating the entire data each time.
See also append() and prepend().
This is an overloaded member function, provided for convenience.
Appends the string str onto the end of this byte array and returns a reference to this byte array. The Unicode data is converted into 8-bit characters using QString::toAscii().
If the QString contains non-ASCII Unicode characters, using this operator can lead to loss of information. You can disable this operator by defining QT_NO_CAST_TO_ASCII when you compile your applications. You then need to call QString::toAscii() (or QString::toLatin1() or QString::toUtf8() or QString::toLocal8Bit()) explicitly if you want to convert the data to const char *.
This is an overloaded member function, provided for convenience.
Appends the string str onto the end of this byte array and returns a reference to this byte array.
This is an overloaded member function, provided for convenience.
Appends the character ch onto the end of this byte array and returns a reference to this byte array.
Returns true if this byte array is lexically less than string str; otherwise returns false.
The Unicode data is converted into 8-bit characters using QString::toAscii().
The comparison is case sensitive.
You can disable this operator by defining QT_NO_CAST_FROM_ASCII when you compile your applications. You then need to call QString::fromAscii(), QString::fromLatin1(), QString::fromUtf8(), or QString::fromLocal8Bit() explicitly if you want to convert the byte array to a QString before doing the comparison.
Returns true if this byte array is lexically less than or equal to string str; otherwise returns false.
The Unicode data is converted into 8-bit characters using QString::toAscii().
The comparison is case sensitive.
You can disable this operator by defining QT_NO_CAST_FROM_ASCII when you compile your applications. You then need to call QString::fromAscii(), QString::fromLatin1(), QString::fromUtf8(), or QString::fromLocal8Bit() explicitly if you want to convert the byte array to a QString before doing the comparison.
Assigns other to this byte array and returns a reference to this byte array.
This is an overloaded member function, provided for convenience.
Assigns str to this byte array.
Returns true if this byte array is equal to string str; otherwise returns false.
The Unicode data is converted into 8-bit characters using QString::toAscii().
The comparison is case sensitive.
You can disable this operator by defining QT_NO_CAST_FROM_ASCII when you compile your applications. You then need to call QString::fromAscii(), QString::fromLatin1(), QString::fromUtf8(), or QString::fromLocal8Bit() explicitly if you want to convert the byte array to a QString before doing the comparison.
Returns true if this byte array is lexically greater than string str; otherwise returns false.
The Unicode data is converted into 8-bit characters using QString::toAscii().
The comparison is case sensitive.
You can disable this operator by defining QT_NO_CAST_FROM_ASCII when you compile your applications. You then need to call QString::fromAscii(), QString::fromLatin1(), QString::fromUtf8(), or QString::fromLocal8Bit() explicitly if you want to convert the byte array to a QString before doing the comparison.
Returns true if this byte array is greater than or equal to string str; otherwise returns false.
The Unicode data is converted into 8-bit characters using QString::toAscii().
The comparison is case sensitive.
You can disable this operator by defining QT_NO_CAST_FROM_ASCII when you compile your applications. You then need to call QString::fromAscii(), QString::fromLatin1(), QString::fromUtf8(), or QString::fromLocal8Bit() explicitly if you want to convert the byte array to a QString before doing the comparison.
Returns the byte at index position i as a modifiable reference.
If an assignment is made beyond the end of the byte array, the array is extended with resize() before the assignment takes place.
Example:
QByteArray ba;
for (int i = 0; i < 10; ++i)
ba[i] = 'A' + i;
// ba == "ABCDEFGHIJ"
The return value is of type QByteRef, a helper class for QByteArray. When you get an object of type QByteRef, you can use it as if it were a char &. If you assign to it, the assignment will apply to the character in the QByteArray from which you got the reference.
See also at().
This is an overloaded member function, provided for convenience.
Same as at(i).
This is an overloaded member function, provided for convenience.
This is an overloaded member function, provided for convenience.
Returns the CRC-16 checksum of the first len bytes of data.
The checksum is independent of the byte order (endianness).
Note: This function is a 16-bit cache conserving (16 entry table) implementation of the CRC-16-CCITT algorithm.
Compresses the data byte array and returns the compressed data in a new byte array.
The compressionLevel parameter specifies how much compression should be used. Valid values are between 0 and 9, with 9 corresponding to the greatest compression (i.e. smaller compressed data) at the cost of using a slower algorithm. Smaller values (8, 7, ..., 1) provide successively less compression at slightly faster speeds. The value 0 corresponds to no compression at all. The default value is -1, which specifies zlib's default compression.
See also qUncompress().
This is an overloaded member function, provided for convenience.
Compresses the first nbytes of data and returns the compressed data in a new byte array.
Uncompresses the data byte array and returns a new byte array with the uncompressed data.
Returns an empty QByteArray if the input data was corrupt.
This function will uncompress data compressed with qCompress() from this and any earlier Qt version, back to Qt 3.1 when this feature was added.
Note: If you want to use this function to uncompress external data compressed using zlib, you first need to prepend four bytes to the byte array that contain the expected length of the uncompressed data encoded in big-endian order (most significant byte first).
See also qCompress().
This is an overloaded member function, provided for convenience.
Uncompresses the first nbytes of data and returns a new byte array with the uncompressed data.
A portable snprintf() function, calls qvsnprintf.
fmt is the printf() format string. The result is put into str, which is a buffer of at least n bytes.
Warning: Call this function only when you know what you are doing since it shows different behavior on certain platforms. Use QString::sprintf() to format a string instead.
See also qvsnprintf() and QString::sprintf().
A safe strcmp() function.
Compares str1 and str2. Returns a negative value if str1 is less than str2, 0 if str1 is equal to str2 or a positive value if str1 is greater than str2.
Special case 1: Returns 0 if str1 and str2 are both 0.
Special case 2: Returns an arbitrary non-zero value if str1 is 0 or str2 is 0 (but not both).
See also qstrncmp(), qstricmp(), qstrnicmp(), and 8-bit Character Comparisons.
Copies all the characters up to and including the '\0' from src into dst and returns a pointer to dst. If src is 0, it immediately returns 0.
This function assumes that dst is large enough to hold the contents of src.
See also qstrncpy().
Returns a duplicate string.
Allocates space for a copy of src, copies it, and returns a pointer to the copy. If src is 0, it immediately returns 0.
Ownership is passed to the caller, so the returned string must be deleted using delete[].
A safe stricmp() function.
Compares str1 and str2 ignoring the case of the characters. The encoding of the strings is assumed to be Latin-1.
Returns a negative value if str1 is less than str2, 0 if str1 is equal to str2 or a positive value if str1 is greater than str2.
Special case 1: Returns 0 if str1 and str2 are both 0.
Special case 2: Returns a random non-zero value if str1 is 0 or str2 is 0 (but not both).
See also qstrcmp(), qstrncmp(), qstrnicmp(), and 8-bit Character Comparisons.
A safe strlen() function.
Returns the number of characters that precede the terminating '\0', or 0 if str is 0.
See also qstrnlen().
A safe strncmp() function.
Compares at most len bytes of str1 and str2.
Returns a negative value if str1 is less than str2, 0 if str1 is equal to str2 or a positive value if str1 is greater than str2.
Special case 1: Returns 0 if str1 and str2 are both 0.
Special case 2: Returns a random non-zero value if str1 is 0 or str2 is 0 (but not both).
See also qstrcmp(), qstricmp(), qstrnicmp(), and 8-bit Character Comparisons.
A safe strncpy() function.
Copies at most len bytes from src (stopping at len or the terminating '\0' whichever comes first) into dst and returns a pointer to dst. Guarantees that dst is '\0'-terminated. If src or dst is 0, returns 0 immediately.
This function assumes that dst is at least len characters long.
See also qstrcpy().
A safe strnicmp() function.
Compares at most len bytes of str1 and str2 ignoring the case of the characters. The encoding of the strings is assumed to be Latin-1.
Returns a negative value if str1 is less than str2, 0 if str1 is equal to str2 or a positive value if str1 is greater than str2.
Special case 1: Returns 0 if str1 and str2 are both 0.
Special case 2: Returns a random non-zero value if str1 is 0 or str2 is 0 (but not both).
See also qstrcmp(), qstrncmp(), qstricmp(), and 8-bit Character Comparisons.
A safe strnlen() function.
Returns the number of characters that precede the terminating '\0', but at most maxlen. If str is 0, returns 0.
This function was introduced in Qt 4.2.
See also qstrlen().
A portable vsnprintf() function. Will call ::vsnprintf(), ::_vsnprintf(), or ::vsnprintf_s depending on the system, or fall back to an internal version.
fmt is the printf() format string. The result is put into str, which is a buffer of at least n bytes.
The caller is responsible to call va_end() on ap.
Warning: Since vsnprintf() shows different behavior on certain platforms, you should not rely on the return value or on the fact that you will always get a 0 terminated string back.
Ideally, you should never call this function but use QString::sprintf() instead.
See also qsnprintf() and QString::sprintf().
This is an overloaded member function, provided for convenience.
Returns true if byte array a1 is not equal to byte array a2; otherwise returns false.
This is an overloaded member function, provided for convenience.
Returns true if byte array a1 is not equal to string a2; otherwise returns false.
This is an overloaded member function, provided for convenience.
Returns true if string a1 is not equal to byte array a2; otherwise returns false.
This is an overloaded member function, provided for convenience.
Returns a byte array that is the result of concatenating string a1 and byte array a2.
This is an overloaded member function, provided for convenience.
Returns a byte array that is the result of concatenating character a1 and byte array a2.
This is an overloaded member function, provided for convenience.
Returns a byte array that is the result of concatenating byte array a1 and byte array a2.
See also QByteArray::operator+=().
This is an overloaded member function, provided for convenience.
Returns a byte array that is the result of concatenating byte array a1 and string a2.
This is an overloaded member function, provided for convenience.
Returns a byte array that is the result of concatenating byte array a1 and character a2.
This is an overloaded member function, provided for convenience.
Returns true if byte array a1 is lexically less than byte array a2; otherwise returns false.
This is an overloaded member function, provided for convenience.
Returns true if byte array a1 is lexically less than string a2; otherwise returns false.
This is an overloaded member function, provided for convenience.
Returns true if string a1 is lexically less than byte array a2; otherwise returns false.
This is an overloaded member function, provided for convenience.
Writes byte array ba to the stream out and returns a reference to the stream.
See also Format of the QDataStream operators.
This is an overloaded member function, provided for convenience.
Returns true if byte array a1 is lexically less than or equal to byte array a2; otherwise returns false.
This is an overloaded member function, provided for convenience.
Returns true if byte array a1 is lexically less than or equal to string a2; otherwise returns false.
This is an overloaded member function, provided for convenience.
Returns true if string a1 is lexically less than or equal to byte array a2; otherwise returns false.
This is an overloaded member function, provided for convenience.
Returns true if byte array a1 is equal to byte array a2; otherwise returns false.
This is an overloaded member function, provided for convenience.
Returns true if byte array a1 is equal to string a2; otherwise returns false.
This is an overloaded member function, provided for convenience.
Returns true if string a1 is equal to byte array a2; otherwise returns false.
This is an overloaded member function, provided for convenience.
Returns true if byte array a1 is lexically greater than byte array a2; otherwise returns false.
This is an overloaded member function, provided for convenience.
Returns true if byte array a1 is lexically greater than string a2; otherwise returns false.
This is an overloaded member function, provided for convenience.
Returns true if string a1 is lexically greater than byte array a2; otherwise returns false.
This is an overloaded member function, provided for convenience.
Returns true if byte array a1 is lexically greater than or equal to byte array a2; otherwise returns false.
This is an overloaded member function, provided for convenience.
Returns true if byte array a1 is lexically greater than or equal to string a2; otherwise returns false.
This is an overloaded member function, provided for convenience.
Returns true if string a1 is lexically greater than or equal to byte array a2; otherwise returns false.
This is an overloaded member function, provided for convenience.
Reads a byte array into ba from the stream in and returns a reference to the stream.
See also Format of the QDataStream operators.
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