Why error message is not displaying
Question
<html>
<head>
<script type="text/javascript">
function validate() {
var a = document.form.name.value;
if(!(a)) {
document.getElementById("errorBox").innerHTML = "*Please fill required";
} else {
document.getElementById("errorBox").innerHTML = "";
}
}
</script>
</head>
<body>
<form method= "post" name="form" onsubmit="return validate();">
Name :<input type="text" id="name" name="name" />
<div id="errorBox"> </div> <br>
<input type="submit" name="submit" value="submit" />
<input type="Reset" name="Reset" />
</body>
Don't know why that error message is not showing?
2 answers
solution1
1 2016-08-18 06:18:12
In javascript, an empty string is not the same as a null value or an undefined ... but they all resolve to false in a condition !
Try this:
if(!a){
// your code
}
Have a look at this fiddle for a working solution: https://jsfiddle.net/wvofbjdk/
If it does not work in your code, then the error is elsewhere. Have a look at the console for errors (see this link to get started on chrome: https://developers.google.com/web/tools/chrome-devtools/debug/console/?hl=en ).
solution2
1 ACCPTED 2016-08-18 06:27:07
Replace your following code
var a = document.form.name.value;
if( a == "" )
{
document.getElementById("errorBox").innerHTML = "*Please fill required";
}
with this code
var a = document.getElementById("name").value;
if(!(a))
{
document.getElementById("errorBox").innerHTML = "*Please fill required";
}
If still issue not solved, kindly show us ur html code so that we check is there any error or not.
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