JavaScript Email Validation
In this section we are going to check email Validation using JavaScript.
JavaScript allows to perform a client side validation of email Ids in several forms. For this purpose, we have created an example which shows how you can validate an email address for a form. The function checkEmail() checks if the entered email id has the general syntax of an email. When user submits the email address then it calls the ValidateEmail() function which validates the email entered by the user in the text box.
Here is the code:
| <html> <h2>Email Validation</h2> <script language = "Javascript"> function checkEmail() { if (/^\w+([\.-]?\w+)*@\w+([\.-]?\w+)*(\.\w{2,3})+$/.test(form.email.value)){ document.write("You have entered valid email."); return true; } return false; } function ValidateEmail(){ var emailID=document.form.email; if ((emailID.value==null)||(emailID.value=="")){ alert("Please Enter your Email ID") emailID.focus() return false } if (checkEmail(emailID.value)==false){ emailID.value="" alert("Invalid Email Adderess"); emailID.focus() return false } return true } </script> <form name="form" method="post" onSubmit="return ValidateEmail()"> Enter an Email Address : <input type="text" name="email" size="30"><br> <input type="submit" name="Submit" value="Submit"> </form> </html> |
Output will be displayed as:
When user enters the invalid email, an alert box is displayed showing error message:

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