Q1047 How do you limit the length (in characters) of text entered in a textarea form field?

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Q1047 How do you limit the length (in characters) of text entered in a textarea form field?

This can't be done whilst the user is entering data into the textarea - only after they have finished:

<script language="JavaScript"><!--
function validate(what) {
    if (what.length > 10) {
        alert('Must be less than 10 characters');
        return false;
    }
    return true;
}
//--></script>

<form name="formName" onSubmit="return validate(documents.formName.textName.value)">
<textarea name="textName" onChange="validate(this.value)"></textarea>
</form>

This isn't true any more for all browsers. You can use onkeypress or onKeyUp for "realtime" checks. It doesn't work on older browsers, so it's best used in addition to a check like the one above:

<textarea onKeyUp="if (this.value.length>30) { alert('Please enter only 30 chars'); this.value=this.value.substring(0,30) }"></textarea>

Feedback on 'Q1047 How do you limit the length (in characters) of text entered in a textarea form field?'

• October 01, 2002 at 18:43:29: Bill Wilkinson
• September 24, 2001 at 12:42:46: Sheldon Hart
• 04:49:05 2/02/00 Frank Mair