paste only numbers in text box using javascript

   In this Example i am Describing , Paste only numbers or numeric in the text box..
here if we copying characters + numbers it will paste (display) only Numbers

Here is the Example

1)First Copy Any data:

2)Paste in second text box

3)final OUTPUT:

Text box onpaste :
------------
onpaste="return paste(this);"

Script:
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function paste(obj) {
            var totalCharacterCount = window.clipboardData.getData('Text');
            var strValidChars = "0123456789";
            var strChar;
            var FilteredChars = "";
            for (i = 0; i < totalCharacterCount.length; i++) {
                strChar = totalCharacterCount.charAt(i);
                if (strValidChars.indexOf(strChar) != -1) {
                    FilteredChars = FilteredChars + strChar;
                }
            }
            obj.value = FilteredChars;
            return false;
        }