QRegExpValidator Class Reference
^{^{[

QtGui

module]}}

The QRegExpValidator class is used to check a string against a regular expression. 更多...

方法

__init__ ( self , QObject parent = None)
__init__ ( self , QRegExp rx , QObject parent = None)
QRegExp regExp ( self )
setRegExp ( self , QRegExp rx )
(QValidator.State, QString input , int pos ) validate ( self , QString input , int pos )
(QValidator.State, int pos ) validate ( self , QString input , int pos )

详细描述

The QRegExpValidator class is used to check a string against a regular expression.

QRegExpValidator uses a regular expression (regexp) to determine whether an input string is Acceptable , 中间体，或 Invalid . The regexp can either be supplied when the QRegExpValidator is constructed, or at a later time.

When QRegExpValidator determines whether a string is Acceptable or not, the regexp is treated as if it begins with the start of string assertion ( ^ ) and ends with the end of string assertion ( $ ); the match is against the entire input string, or from the given position if a start position greater than zero is given.

If a string is a prefix of an Acceptable string, it is considered 中间体 . For example, "" and "A" are 中间体 for the regexp [A-Z][0-9] (whereas " _ " would be Invalid ).

For a brief introduction to Qt's regexp engine, see QRegExp .

用法范例：

 // regexp: optional '-' followed by between 1 and 3 digits
 QRegExp rx("-?\\d{1,3}");
 QValidator *validator = new QRegExpValidator(rx, this);
 QLineEdit *edit = new QLineEdit(this);
 edit->setValidator(validator);

Below we present some examples of validators. In practice they would normally be associated with a widget as in the example above.

 // integers 1 to 9999
 QRegExp rx("[1-9]\\d{0,3}");
 // the validator treats the regexp as "^[1-9]\\d{0,3}$"
 QRegExpValidator v(rx, 0);
 QString s;
 int pos = 0;
 s = "0";     v.validate(s, pos);    // returns Invalid
 s = "12345"; v.validate(s, pos);    // returns Invalid
 s = "1";     v.validate(s, pos);    // returns Acceptable
 rx.setPattern("\\S+");            // one or more non-whitespace characters
 v.setRegExp(rx);
 s = "myfile.txt";  v.validate(s, pos); // Returns Acceptable
 s = "my file.txt"; v.validate(s, pos); // Returns Invalid
 // A, B or C followed by exactly five digits followed by W, X, Y or Z
 rx.setPattern("[A-C]\\d{5}[W-Z]");
 v.setRegExp(rx);
 s = "a12345Z"; v.validate(s, pos);        // Returns Invalid
 s = "A12345Z"; v.validate(s, pos);        // Returns Acceptable
 s = "B12";     v.validate(s, pos);        // Returns Intermediate
 // match most 'readme' files
 rx.setPattern("read\\S?me(\.(txt|asc|1st))?");
 rx.setCaseSensitive(false);
 v.setRegExp(rx);
 s = "readme";      v.validate(s, pos); // Returns Acceptable
 s = "README.1ST";  v.validate(s, pos); // Returns Acceptable
 s = "read me.txt"; v.validate(s, pos); // Returns Invalid
 s = "readm";       v.validate(s, pos); // Returns Intermediate

方法文档编制

QRegExpValidator.init ( self , QObject parent = None)

parent argument, if not None, causes self to be owned by Qt instead of PyQt.

构造验证器采用 parent object that accepts any string (including an empty one) as valid.

QRegExpValidator.init ( self , QRegExp rx , QObject parent = None)

parent argument, if not None, causes self to be owned by Qt instead of PyQt.

构造验证器采用 parent object that accepts all strings that match the regular expression rx .

The match is made against the entire string; e.g. if the regexp is [A-Fa-f0-9]+ it will be treated as ^[A-Fa-f0-9]+$ .

QRegExp QRegExpValidator.regExp ( self )

QRegExpValidator.setRegExp ( self , QRegExp rx )

( QValidator.State , QString input , int pos ) QRegExpValidator.validate ( self , QString input , int pos )

重实现自 QValidator.validate ().

返回 Acceptable if input is matched by the regular expression for this validator, 中间体 if it has matched partially (i.e. could be a valid match if additional valid characters are added), and Invalid if input 不是 matched.

pos parameter is set to the length of the input 参数。

For example, if the regular expression is \w\d\d (word-character, digit, digit) then "A57" is Acceptable , "E5" is 中间体 , and "+9" is Invalid .

另请参阅 QRegExp.exactMatch ().

QRegExpValidator Class Reference [ QtGui module]

方法