QIntValidator Class

详细描述

The QIntValidator class provides a validator that ensures a string contains a valid integer within a specified range.

Example of use:

  QValidator *validator = new QIntValidator(100, 999, this);
  QLineEdit *edit = new QLineEdit(this);

  // the edit lineedit will only accept integers between 100 and 999
  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.

  QString str;
  int pos = 0;
  QIntValidator v(100, 900, this);

  str = "1";
  v.validate(str, pos);     // returns Intermediate
  str = "012";
  v.validate(str, pos);     // returns Intermediate

  str = "123";
  v.validate(str, pos);     // returns Acceptable
  str = "678";
  v.validate(str, pos);     // returns Acceptable

  str = "999";
  v.validate(str, pos);    // returns Intermediate

  str = "1234";
  v.validate(str, pos);     // returns Invalid
  str = "-123";
  v.validate(str, pos);     // returns Invalid
  str = "abc";
  v.validate(str, pos);     // returns Invalid
  str = "12cm";
  v.validate(str, pos);     // returns Invalid

Notice that the value 999 returns Intermediate. Values consisting of a number of digits equal to or less than the max value are considered intermediate. This is intended because the digit that prevents a number from being in range is not necessarily the last digit typed. This also means that an intermediate number can have leading zeros.

The minimum and maximum values are set in one call with setRange(), or individually with setBottom() and setTop().

QIntValidator uses its locale() to interpret the number. For example, in Arabic locales, QIntValidator will accept Arabic digits.

Note: The QLocale::NumberOptions set on the locale() also affect the way the number is interpreted. For example, since QLocale::RejectGroupSeparator is not set by default, the validator will accept group separators. It is thus recommended to use QLocale::toInt() to obtain the numeric value.