ignoreCase Property

Returns a Boolean value indicating the state of the ignoreCase flag (i) used with a regular expression.

rgExp.ignoreCase

Arguments

  • rgExp
    Required. An instance of a Regular Expression object.

Remarks

The ignoreCase property is read-only, and returns true if the ignoreCase flag is set for a regular expression, and returns false if it is not. The default value is false.

The ignoreCase flag, when used, indicates that a search should ignore case sensitivity when matching the pattern within the searched string.

Example

The following example illustrates the use of the ignoreCase property. If you pass gi in to the function shown below, all instances of the word "the" are replaced with the word "a", including the initial "The". This is because with the ignoreCase flag set, the search ignores any case sensitivity. So "T" is the same as "t" for the purposes of matching.

This function returns the Boolean values that indicate the state of the allowable regular expression flags, which are g, i, and m. The function also returns the string with all replacements made.

function RegExpPropDemo(flag){
    // The flag parameter is a string that contains
    // g, i, or m.  The flags can be combined.

    // Check flags for validity.
    if (flag.match(/[^gim]/))
        {
        return ("Flag specified is not valid");
        }

    // Create the string on which to perform the replacement.
    var orig = "The batter hit the ball with the bat ";
    orig += "and the fielder caught the ball with the glove.";

    //Replace "the" with "a".
    var re = new RegExp("the", flag);
    var r = orig.replace(re, "a");        

    // Output the resulting string and the values of the flags.
    print("global: " + re.global.toString());
    print("ignoreCase: " + re.ignoreCase.toString());
    print("multiline: " + re.multiline.toString());
    print("Resulting String: " + r);
}

RegExpPropDemo("gi");
RegExpPropDemo("g");

The resulting output is the following:

global: true
ignoreCase: true
multiline: false
Resulting String: a batter hit a ball with a bat and a fielder caught a ball with a glove.

global: true
ignoreCase: false
multiline: false
Resulting String: The batter hit a ball with a bat and a fielder caught a ball with a glove.

Requirements

Version 5.5

Applies To:

Regular Expression Object

See Also

Concepts

Regular Expression Syntax

Reference

global Property

multiline Property

Change History

Date

History

Reason

July 2009

Modified example.

Content bug fix.

March 2009

Modified example.

Information enhancement.