Though it is a very common question. I have one input field in which the data entered must be between 1 and 150.
Problem is I am already using some validations on that. That validation is being used by many other input fields. So I cannot change that. It is the num() function.
On one field mesure I want to add extra functionality. I tried it with validate. I don't know how to merge these two validations for only one input field using both function in document.ready.
I can do it in either jQuery or PHP.
<input type="text" name='mesure' class="numbersonly" maxlength="3" onblur =" validate()"/>
function num() {
$(".numbersonly").bind('keypress', function(e) {
if (e.which != 8 && e.which != 0 && (e.which < 48 || e.which > 57)) {
$("#errmsg").html("numbers please");
return false;
}
});
}
function validate()
{
if( document.form.mesure.value >150 )
{
alert( "out of range!" );
document.form.mesure.focus() ;
return false;
}
}
Why not using onkeypress/onkeyup, check it using the validate function. But remember that javascript is not the real solution for limitation - People can turn of or change the javascript. Also use php for checking the value.
For example, if your input field that you want to limit has the id #text, you can use
if($('#text').val().length>150){
//do stuff here
}
As you will probably post the entered value to some place in the backend, the real validation must happen in php. There, you can do something like
<?php
if(strlen($_POST['text'])>150){
echo "too long";
exit;
}
//do other backend stuff here
?>
Using javascript for validation is only good in so far as it gives the user immediate feedback whether he did something wrong. However, a client can always see client side code like jQuery/Javascript, so for ultimate validation use php.