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how to pass the javascript variable to textbox?

i would like to ask a question.

how can i pass the javascript generated code to the textbox "code" ?

I surf the internet but I cannot find the answer

I hope all of you can help me.

thanks!!

  <form><input name="code" type="text" value="" >
                <script>
                    function makeid()
                    {
                        var text = "";
                        var possible = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";

                        for( var i=0; i < 6; i++ )
                            text += possible.charAt(Math.floor(Math.random() * possible.length));

                        alert(text);
                        return text;
                    }       
                </script>
                  <input type="button" style="font-size:9pt" value="Generate Code" onclick="makeid()">
                  </input></form>

You have to set the value of the text box, rather than returning the value

The updated code,

var codeElem = document.getElementById('code');

function makeid() {
  var text = "", possible = "ABCDEFGHIJKLMNOPQRSTUVWXYZ", i = 0;

  for( ; i < 6; i++ ) {
    text += possible.charAt(Math.floor(Math.random() * possible.length));
  }

  //alert(text);

  codeElem.value = text;
}​

You've to add an id attribute to the text box, so that it can be accessed easily.

<input id="code" name="code" type="text" value="" >

Working example

You need to set that textbox's value value. If its id was code , you could just do this:

document.getElementById('code').value = text;

But as it stands, you'll have to cycle through all inputs to look for it:

var inputs = document.getElementsByTagName('input'),
    i = inputs.length;

while (i) {
    i -= 1;
    if (inputs[i].name === 'code') {
        inputs[i].value = text;
        break;
    }
}

The following code change for the two input fields will cause the random string to appear in the input text field, in addition to the alert box:

<input name="code" id="code" type="text" value="" >
<!-- original javascript code goes here-->
<input type="button" style="font-size:9pt" value="Generate Code" 
    onclick="document.getElementById('code').value = makeid()">

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