javascript - 显示需要用户名和密码的消息是什么？

Question

我不知道如何显示需要用户名和密码的消息!

当我点击“提交”时，它会自动打开到index.php

它应该显示我需要用户名和密码

这是我的代码:

var username = document.form["vform"]["username"];
var email = document.form["vform"]["email"];
var password = document.form["vform"]["password"];
var password_confirmation = document.form["vform"]["password_confirmation"];



var name_error = document.getElementById("name_error");
var email_error = document.getElementById("email_error");
var password_error = document.getElementById("password_error");


username.addEventListener("blur", nameVerify, true);
email.addEventListener("blur", emailVerify, true);
password.addEventListener("blur", passwordVerify, true);



function Validate() {
    if (username.value == "") {
        username.style.border = "1px solid red";
        name_error.textContent = "Username is required";
        name.focus();
        return false;

    }


    if (email.value == "") {
        email.style.border = "1px solid red";
        email_error.textContent = "Email is required";
        email.focus();
        return false;

    }




    if (password.value == "") {
        password.style.border = "1px solid red";
        password_error.textContent = "Password is required";
        password.focus();
        return false;

    }


    // Check if two password match
    if (password.value != password_confirmation.value) {
        password.style.border = "1px solid red";
        password_confirmation.style.border = "1px solid red";
        password_error.innerHTML = "The two passwords don't match";
        return false;

    }
}


function nameVerify() {
    if (username.value != "") {
        username.style.border = "1px solid #5E6E66";
        name_error.innerHTML = "";
        return true;
    }
}


function emailVerify() {
    if (email.value != "") {
        email.style.border = "1px solid #5E6E66";
        email_error.innerHTML = "";
        return true;
    }
}


function passwordVerify() {
    if (password.value != "") {
        password.style.border = "1px solid #5E6E66";
        password_error.innerHTML = "";
        return true;
    }
}

我没有看到错误在哪里，我认为这很好，没有语法错误，也许缺少了一些东西。

Answer 1

确保您的表单具有 required attribute (HTML5):

<input type="text" name="username" required />
<input type="text" name="password" required />

无需 JavaScript 验证。确保也在服务器端进行验证。