服务器控件增加脚本

后台

//定义公共变量
public string dropIsSmokeClientID ;  //(DroptDownList)
public string txtSmokeAgeClientID ;  //(Textbox)

//给变量赋值
dropIsSmokeClientID = dropIsSmoke.ClientID;
txtSmokeAgeClientID = txtSmokeAge.ClientID;

//给服务器控件增加脚本
dropIsSmoke.Attributes.Add("onchange", "return IsSmoke()");

前台脚本
<script language="javascript">
function IsSmoke()
{
    //前台找服务器控件
    var SmokeValue=document.getElementById('<%=dropIsSmokeClientID %>');
    var SmokeAge=document.getElementById('<%=txtSmokeAgeClientID %>');
    if(SmokeValue.value=="1")
    {
        SmokeAge.disabled=false;
    }
    else
    {
       SmokeAge.disabled=true;
    }
}
   
</script>