[英]Trying to validate username and password in javascript but not getting alert and desired output
请检查代码
function validate() { var name = document.getElementById("name"); var pwd = document.getElementById("pwd"); if (name == null || name == "") { alert("Name can't be blank"); return false; } else if (pwd.length < 6) { alert("Password must be at least 6 characters long."); return false; } }
<form> username: <input type="text" id="name"></input> <br> password: <input type="password" id="pwd"></input> <br> <button onclick="validate()">Submit</button> </form>
function validate() { var name = document.getElementById("name").value; var pwd = document.getElementById("pwd").value; if (name === null || name === "") { alert("Name can't be blank"); return false; } else if (pwd.length < 6) { alert("Password must be at least 6 characters long."); return false; } }
<form> username: <input type="text" id="name"></input> <br> password: <input type="password" id="pwd"></input> <br> <button onclick="validate()">Submit</button> </form>
有一种更简单的方法可以做你想做的事情。 您可以使用form
的原生属性来发挥自己的优势:
<form> Username: <input type="text" minlength="2" required> <br> Password: <input type="password" minlength="6" required> <br> <button type="submit">Submit</button> </form>
<!DOCTYPE html>
<html>
<body>
<form>
username: <input type="text" id="name"></input>
<br>
password: <input type="password" id="pwd"></input>
<br>
<button onclick="validate()">Submit</button>
</form>
<script>
function validate() {
var name = document.getElementById("name").value;
var pwd = document.getElementById("pwd").value;
if (name == null || name == "") {
alert("Name can't be blank");
return false;
} else if (pwd.length < 6) {
alert("Password must be at least 6 characters long.");
return false;
}
}
</script>
</body>
</html>
您还没有提供完整的代码,所以我们无法真正帮助您。 据我所知,您没有发出成功验证的警报。
您需要获取该值,因此您需要将 add.value 添加到 getElement 函数中。
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