Javascript 输入更改时如何运行javascript函数
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How can I run a javascript function when input changes
提问by mamrezo
When a user creates a new account on my website I want to check if the name already exists. I want this check to run when they leave the username input box and go to enter a password.
当用户在我的网站上创建新帐户时，我想检查该名称是否已存在。我希望在他们离开用户名输入框并输入密码时运行此检查。
I tried :
我试过 ：
<input type="text" onkeyup="check_user(this.value)"/>
采纳答案by Please treat your mods well.
You need to use the "onblur" event. It fires when a control loses its focus, which seems to be exactly what you need.
您需要使用“onblur”事件。它在控件失去焦点时触发，这似乎正是您所需要的。
回答by Awais Qarni
Call the function on the changeevent of text field:
在change文本字段的事件上调用函数：
<input name="username" onChange="check_user(this.value);" type="text"/>
回答by Ben
Because you used onkeyupin your code example, it sounds like you are looking to call a function on every keystroke. If that is the case, then instead of onchange- which fires when the inputloses focus - you should use oninputwhich will fire anytime there is a change inside of input.
因为您onkeyup在代码示例中使用过，所以听起来您希望在每次击键时调用一个函数。如果是这种情况，那么代替onchange- 在input失去焦点时触发- 您应该使用oninputwhich 将在输入内部发生变化时触发。
回答by enthusiastic
I think you are looking for check the duplication of user. you have to write server side code for that.
我认为您正在寻找检查用户的重复。您必须为此编写服务器端代码。
