It is used to check that entered data of an application form is valid or not, for example, if we enter mobileno and emailid then format of email id and mobile no is correct or not it will be managed by Validation.
Now HTML5 Validation is working in form but it is not applied for all conditions,if we want to create custom validation logic then we will use Javascript or Jquery.
Now we are creating a registration form with all possible validation process
<!DOCTYPE html>
<html>
<head>
<title></title>
<style type="text/css">
span
{
color:red;
}
</style>
<script type="text/javascript">
function validate()
{
name = document.getElementById("txtname").value;
pass = document.getElementById("txtpass").value;
cpass = document.getElementById("txtcpass").value;
email = document.getElementById("txtemail").value;
mobile = document.getElementById("txtmobile").value;
atpos = email.indexOf("@");
dotpos = email.lastIndexOf(".");
if(name.length==0)
{
document.getElementById("spname").innerHTML="Enter name first";
return false;
}
if(pass.length<5)
{
document.getElementById("sppass").innerHTML="Password length should be above five";
return false;
}
if(pass!=cpass)
{
document.getElementById("sppass").innerHTML="Password Mismatch from confirm password";
return false;
}
if(isNaN(mobile))
{
document.getElementById("spmobile").innerHTML="Mobile number should be numeric";
return false;
}
if(mobile.length!=10)
{
document.getElementById("spmobile").innerHTML="Mobile number should be 10 digit";
return false;
}
if(atpos==-1 || dotpos == -1 || dotpos<atpos || (dotpos-atpos)<2)
{
document.getElementById("spemail").innerHTML="Invalid emailid";
return false;
}
}
</script>
</head>
<body>
<form action="addition.html">
<input type="text" id="txtname" placeholder="Enter name" /><span id="spname"></span>
<br>
<br>
<input type="password" id="txtpass" placeholder="Enter password" /><span id="sppass"></span>
<br>
<br>
<input type="password" id="txtcpass" placeholder="Enter confirm password" />
<br>
<br>
<input type="text" id="txtmobile" placeholder="Enter mobileno" /><span id="spmobile"></span>
<br>
<br>
<input type="text" id="txtemail" placeholder="Enter emailid" /><span id="spemail"></span>
<br>
<br>
<input type="submit" id="btnsubmit" value="Click" onclick="return validate()" >
</body>
</html>
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