Table of Contents
How to use QString in Qt 4.8?
Public Functions QString () ~QString () QString & append ( const QString & str ) QString & append ( const QStringRef & reference ) QString & append ( const QLatin1String & str )
Which is QString function returns a const char?
QString provides the following three functions that return a const char * version of the string as QByteArray: toUtf8(), toLatin1(), and toLocal8Bit(). toLatin1() returns a Latin-1 (ISO 8859-1) encoded 8-bit string. toUtf8() returns a UTF-8 encoded 8-bit string.
What is the QString ARG function in Qt 5.10?
This function was introduced in Qt 5.10. QString QString:: arg (const QString &a1, const QString &a2) const. This function overloads arg(). This is the same as str.arg(a1).arg(a2), except that the strings a1 and a2 are replaced in one pass. This can make a difference if a1 contains e.g. %1:
How to find the index of a string in QString?
int QString:: indexOf (const QRegularExpression &re, int from = 0) const. This function overloads indexOf(). Returns the index position of the first match of the regular expression re in the string, searching forward from index position from. Returns -1 if re didn’t match anywhere. Example:
How is a const char interpreted in QString?
QString converts the const char * data into Unicode using the fromUtf8 () function. In all of the QString functions that take const char * parameters, the const char * is interpreted as a classic C-style ‘\\0’-terminated string encoded in UTF-8. It is legal for the const char * parameter to be nullptr.
How do you initialize a QString in Java?
One way to initialize a QString is simply to pass a const char * to its constructor. For example, the following code creates a QString of size 5 containing the data “Hello”: QString converts the const char * data into Unicode using the fromAscii () function.
When to return the whole string in QString?
QString QString:: left (int n) const. Returns a substring that contains the n leftmost characters of the string. The entire string is returned if n is greater than or equal to size(), or less than zero.