how to restrict the user to enter only 250 words in text area?

Question

i have created one form for user to submit a abstract. but while submitting i need to check weather they have added more than 250 words or not. i need to allow only 250 words . how to do this ?

i have tried some JavaScript but it works for only 250 character.

here is my code

function maxlength(element, maxvalue)
   {
  var q = eval("document.upload."+element+".value.length");
   var r = q - maxvalue;
   var msg = "Sorry, you have input "+q+" characters into the "+
  "text area box you just completed. It can return no more than "+
  maxvalue+" words to be processed. Please abbreviate "+
 "your text by at least "+r+" words";
    if (q > maxvalue) alert(msg);
      }

and my textarea is :

  <tr>
   <td><label>Abstract Details</label> </td>
 <td><label>Please enter data, at most 250 words:</label>
  <br/><textarea rows="6" cols="80"name="box_name"   onChange="maxlength('box_name', 250)" style="width: 257px; height: 131px;">    </textarea></td>
    </tr>
  <tr>

how to limit for 250 words .

thanks in advance

Answer 1

To prevent submitting form when there is more than 250 characters in the textarea, add id="box_id" to your textarea and add this event to form element:

onsubmit="return maxlength(getElementById('box_id'), 250);

Now in your function split this value by multiple spaces:

function maxlength(element, maxvalue){
    var q = element.value.split(/[\s]+/).length;
    if(q > maxvalue){
        var r = q - maxvalue;
        alert("Sorry, you have input "+q+" words into the "+
        "text area box you just completed. It can return no more than "+
        maxvalue+" words to be processed. Please abbreviate "+
        "your text by at least "+r+" words");
        return false;
    }
}

To take advantage from new HTML attributes, you can also add "pattern" attribute to textarea with regex limiting input to 250 words:

<textarea rows="6" cols="80"name="box_name"   onChange="maxlength(this, 250)" style="width: 257px; height: 131px;" 
    pattern="^(?:\b\w+\b[\s\r\n]*){1,250}$">
</textarea>

This regex pattern was taken from following SO thread, which touches similar problem with 250 words: Limit the number of words in a response with a regular expression

Answer 2

use this:

function maxlength(element, maxvalue)
{
    var value = $(elment).val();
    var words = value.split(' ');

    var msg = 'Sorry, you have input ' + words.length + ' words into the ' +
        'text area you just completed. It can return no more than ' +
        maxvalue + ' words to be processed. Please abbreviate ' +
        'your text by at least ' + (words.length - maxvalue) + ' words';

    if (words.length > maxvalue) {
        alert(msg);
    }
}