This page is Ready to Use

Notice: The WebPlatform project, supported by various stewards between 2012 and 2015, has been discontinued. This site is now available on github.

1...9 Properties

Summary

Return the nine most-recently memorized portions found during pattern matching. Read-only.

Syntax

RegExp.$ n
'RegExp’
Always the global RegExp object.
n
Any integer from 1 through 9.

Examples

The following example performs a regular expression search. It displays matches and submatches from the global RegExp object. The submatches are successful parenthesized matches that are contained in the properties. The example also displays matches and submatches from the array that is returned by the exec method.

var newLine = "<br />";

 var re = /(\w+)@(\w+)\.(\w+)/g
 var src = "Please send mail to george@contoso.com and someone@example.com. Thanks!"

 var result;
 var s = "";

 // Get the first match.
 result = re.exec(src);

 while (result != null) {
     // Show the entire match.
     s += newLine;

     // Show the match and submatches from the RegExp global object.
     s += "RegExp.lastMatch: " + RegExp.lastMatch + newLine;
     s += "RegExp.: " + RegExp. + newLine;
     s += "RegExp.: " + RegExp. + newLine;
     s += "RegExp.: " + RegExp. + newLine;

     // Show the match and submatches from the array that is returned
     // by the exec method.
     for (var index = 0; index < result.length; index++) {
         s +=  index + ": ";
         s += result[index];
         s += newLine;
     }

     // Get the next match.
     result = re.exec(src);
 }
 document.write(s);

 // Output:
 //  RegExp.lastMatch: george@contoso.com
 //  RegExp.: george
 //  RegExp.: contoso
 //  RegExp.: com
 //  0: george@contoso.com
 //  1: george
 //  2: contoso
 //  3: com

 //  RegExp.lastMatch: someone@example.com
 //  RegExp.: someone
 //  RegExp.: example
 //  RegExp.: com
 //  0: someone@example.com
 //  1: someone
 //  2: example
 //  3: com

Remarks

The values of the $1…$9 properties are modified whenever a successful parenthesized match is made. Any number of parenthesized substrings may be specified in a regular expression pattern, but only the nine most recent can be stored.

Attributions

  • Microsoft Developer Network: Article