html - 如何更改 Bootstrap 中表单控件弹出窗口中必填字段的默认消息？

Question

 <form class="form-asd" role="form">
    <h2 class="form-signin-heading">login</h2><hr />
    <label class="control-label"  for="username">Username</label>
    <input class="form-control" type="email"  required="" placeholder="username"data-error="enter username"></input>
    <label class="control-label"  for="username">password</label>
    <input class="form-control" type="password"  required=" " placeholder="Password"></input>
    <label class="checkbox"></label>
    <button class="btn btn-lg btn-primary " type="submit">submit</button>
</form>

我们如何将要求字段的弹出窗口的默认消息“请填写此字段”更改为“请输入用户名”

Answer 1

当oninvalid事件发生时，您可以使用setCustomValidity函数。

如下所示:-

<input class="form-control" type="email" required="" 
    placeholder="username" oninvalid="this.setCustomValidity('Please Enter valid email')">
</input>

更新:-

要在开始输入后清除消息，请使用 oninput="setCustomValidity('') 属性清除消息。

<input class="form-control" type="email"  required="" placeholder="username"
 oninvalid="this.setCustomValidity('Please Enter valid email')"
 oninput="setCustomValidity('')"></input>