要检查某个字段是否有效，请使用:

To check whether a certain field is valid, use:

$('#myField')[0].checkValidity(); // returns true|false

要检查表单是否有效，请使用:

To check if the form is valid, use:

$('#myForm')[0].checkValidity(); // returns true|false

如果您想显示某些浏览器(例如 Chrome)的本机错误消息，不幸的是，唯一的方法是提交表单，如下所示:

If you want to display the native error messages that some browsers have (such as Chrome), unfortunately the only way to do that is by submitting the form, like this:

var $myForm = $('#myForm');

if (!$myForm[0].checkValidity()) {
    // If the form is invalid, submit it. The form won't actually submit;
    // this will just cause the browser to display the native HTML5 error messages.
    $myForm.find(':submit').click();
}

请记住，目前并非所有浏览器都支持 HTML5 验证.

Keep in mind that, HTML5 validation is not supported in all browsers till now.