


How Can JavaScript Prevent Form Submission and Redirect to the Previous Page on Validation Failure?
Dec 22, 2024 pm 09:55 PMPreventing Form Submission in JavaScript
Question:
In a JavaScript form validation scenario, how can you prevent form submission and return to the previous page when a certain condition is met?
Answer:
There are several approaches to resolve this issue:
Method 1: Using preventDefault() and a Validation Function
<form onsubmit="event.preventDefault(); validateMyForm();">
In this method, validateMyForm() should return false if the validation fails.
Method 2: Returning a Value from the Validation Function
<form name="myForm" onsubmit="return validateMyForm();">
In this script:
function validateMyForm() { if (condition fails) { alert("Validation failed!"); returnToPreviousPage(); return false; } alert("Validation passed!"); return true; }
Method 3: Setting the returnValue Property (Needed for Chrome 27.0.1453.116 m)
function validateMyForm() { if (condition fails) { alert("Validation failed!"); returnToPreviousPage(); event.preventDefault(); event.returnValue = false; // Set `returnValue` to false } alert("Validation passed!"); return true; }
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