我有一个扩展程序控件,OnTextChanged
在用户输入完成后500ms 引发文本框的事件.这个问题是OnTextChanged
当文本框失去焦点时会引发问题,这会导致问题(因为回发).
我想做的是给扩展器控制它自己的服务器端事件(比如说OnDelayedSubmit
),所以我可以单独处理它.该事件将起源于扩展器控件的行为脚本(在500ms延迟之后),因此放入__doPostBack
in onchanged
不是一个选项.
任何人都可以阐明如何解决这个问题吗?
在充分阅读了扩展程序控件和JavaScript之后,我拼凑了一个迄今为止似乎正在运行的解决方案.
主要技巧是从服务器端获取必要的回发代码到客户端行为脚本.我通过使用ExtenderControlProperty
(在控件的OnPreRender
函数中设置),然后在行为脚本中进行评估来完成此操作.剩下的就是基本的事件处理.
所以现在我的扩展控件的.cs
文件看起来像这样:
public class DelayedSubmitExtender : ExtenderControlBase, IPostBackEventHandler { // This is where we'll give the behavior script the necessary code for the // postback event protected override void OnPreRender(EventArgs e) { string postback = Page.ClientScript.GetPostBackEventReference(this, "DelayedSubmit") + ";"; PostBackEvent = postback; } // This property matches up with a pair of get & set functions in the behavior script [ExtenderControlProperty] public string PostBackEvent { get { return GetPropertyValue("PostBackEvent", ""); } set { SetPropertyValue ("PostBackEvent", value); } } // The event handling stuff public event EventHandler Submit; // Our event protected void OnSubmit(EventArgs e) // Called to raise the event { if (Submit != null) { Submit(this, e); } } public void RaisePostBackEvent(string eventArgument) // From IPostBackEventHandler { if (eventArgument == "DelayedSubmit") { OnSubmit(new EventArgs()); } } }
我的行为脚本看起来像这样:
DelayedSubmitBehavior = function(element) { DelayedSubmitBehavior.initializeBase(this, [element]); this._postBackEvent = null; // Stores the script required for the postback } DelayedSubmitBehavior.prototype = { // Delayed submit code removed for brevity, but normally this would be where // initialize, dispose, and client-side event handlers would go // This is the client-side part of the PostBackEvent property get_PostBackEvent: function() { return this._postBackEvent; }, set_PostBackEvent: function(value) { this._postBackEvent = value; } // This is the client-side event handler where the postback is initiated from _onTimerTick: function(sender, eventArgs) { // The following line evaluates the string var as javascript, // which will cause the desired postback eval(this._postBackEvent); } }
现在,服务器端事件的处理方式与处理任何其他控件上的事件的方式相同.