Form Validation

Limit minimum length

if (document.form1.password.value.length < 6)

{

alert("Please give a Password more than 5 characters");

                document.form1.password.focus();

                return false;

}

Confirm Password

if ((document.form1.pass.value) != (document.form1.r_pass.value))

{

                alert("Your password does not match");

                document.form1.r_pass.value == "";

                document.form1.r_pass.focus();

                return false;

            }

            return( true );

Restrict a field to accept Numeric

function isNumeric(elem, helperMsg){

  var numericExpression = /^[0-9]+$/;

  if(elem.value.match(numericExpression)){

  return true;

  }else{

  alert(helperMsg);

  elem.focus();

  return false;

  }

}

..............................................................

Complete Example

<script type='text/javascript'>

function isNumeric(elem, helperMsg){

  var numericExpression = /^[0-9]+$/;

  if(elem.value.match(numericExpression)){

  return true;

  }else{

  alert(helperMsg);

  elem.focus();

  return false;

  }

}

</script>

<form>

Numbers Only: <input type='text' id='numbers'/>

<input type='button'

  onclick="isNumeric(document.getElementById('numbers'), 'Numbers Only Please')"

  value='Check Field' />

</form>

Restrict a field to accept Alphabets

function isAlphabet(elem, helperMsg){

  var alphaExp = /^[a-zA-Z]+$/;

  if(elem.value.match(alphaExp)){

  return true;

  }else{

  alert(helperMsg);

  elem.focus();

  return false;

  }

}

COMPLETE EXAMPLE

<script type='text/javascript'>

function isAlphabet(elem, helperMsg){

  var alphaExp = /^[a-zA-Z]+$/;

  if(elem.value.match(alphaExp)){

  return true;

  }else{

  alert(helperMsg);

  elem.focus();

  return false;

  }

}

</script>

<form>

Letters Only: <input type='text' id='letters'/>

<input type='button'

  onclick="isAlphabet(document.getElementById('letters'), 'Letters Only Please')"

  value='Check Field' />

</form>