JavaScript Find a Word
From Regex Regular Expression Encyclopedia
You can use this recipe for finding single words in a block of text. The expression will find only complete words surrounded by spaces or other word delimiters, such as punctuation or the beginning or end of a line.
[edit] code
<html> <head> <title></title> </head> <body> <form name="form1"> <input type="textbox" name="txtInput" /> <script type="text/javascript"> function validate() { if (! document.form1.txtInput.value.match(/\bsomething\b/)) { alert("Please enter valid value!") } else { alert("Success!") } } </script> <input type="button" name="btnSubmit" onclick="validate()" value="Go" /> </form> </body> </html>
[edit] How It Works
A special character class, \b, allows you to easily search for whole words. This is an advantage because without doing a whole bunch of extra work you can make sure that a search for some- thing, for example, doesn’t yield unexpected matches such as somethings. You can break the regular expression shown here into the following:
| Regular Expression | Description |
|---|---|
| \b | a word boundary (a space, beginning of a line, or punctuation) . . . |
| something | s, o, m, e, t, h, i, n, and g . . . |
| \b | a word boundary at the end of the word. |
This expression differs just slightly from the C# and Visual Basic .NET examples because the RegularExpressionValidator control assumes that the expression is to match the entire value (there’s an implied ^ at the beginning of the expression and $ at the end of the expres- sion). The combination .* has been added before and after the word boundary \b so the full word can float around inside the line.
