所选项目更改事件未触发下拉列表 [英] selected item change event not firing of dropdownlist

问题描述

朋友，
我在触发dropdownlist事件时遇到问题
我有以下下拉菜单

hi friends,
i have a problem in firing dropdownlist event
i have following dropdown

<asp:dropdownlist id="ddlhello" Runat="server" AutoPostBack="True"  onchange="javascript:return ChangeHeader();">

我还在代码后面添加了事件，即selectedindex更改事件.

现在，当我执行该页面时会发生问题，它会执行javascript，但是不会触发服务器端代码，但是如果我删除此行onchange="javascript:return ChangeHeader();"，则将触发服务器端代码.

当我检查源页面时，它向我显示了两个关联的onchange事件
一个用于javascript，另一个用于服务器端.

我认为这是在选择客户端代码，而忽略了服务器端.

我不太确定，所以我想知道行为原因.
而这的出路是什么.

我希望执行服务器和客户端代码.
我一直在寻找解决方案，但没有找到任何正确的原因. 请同样答复.在此先感谢

i have also added event in code behind i.e. selectedindex change event.

Now problem occurs when i execute the page, it executes javascript but server side code doesnot fire, but if i remove this line onchange="javascript:return ChangeHeader();" then server side code fires.

when i checked source page it shows me two onchange events associated
one for javascript and other for server side.

i think that it is picking client side code and neglects server side.

I am not pretty sure, so i want to know the behavior reason.

And what is the way out for this.

i want server and client side code to be executed.
i have searched for solutions but i have not found any correct reason.
please reply for the same. Thanks in advance

推荐答案

，您可能尚未添加return true；在javascript的ChangeHeader()函数的末尾...

you might have not added return true; at the end of the ChangeHeader() function in javascript...

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