Form Validation
Form submit hone se pehle required input ko JavaScript se validate karo.
Working code
const form = document.querySelector("form");
const nameInput = document.querySelector("#name");
form.addEventListener("submit", (event) => {
if (nameInput.value.trim() === "") {
event.preventDefault();
console.log("Name is required");
}
});Expected output
Empty name submit karne par: Name is required
How it works
Submit event par callback run hota hai.
trim() blank spaces hata kar empty value check karta hai. Invalid input par preventDefault() form submission rok deta hai.
Try Yourself
const email = document.querySelector("#email");
if (email.value.trim() === "") {
console.log("Email is required");
} else {
console.log("Looks good");
}