J
jimmy.liang
hi,
Is there any way to add eventhandler to custom usercontrol and could
set it at webForm?
i can add eventhandler on code, such as at Page_Load, add:
MyControl1.SelectedIndexChanged = this.OnSelectedIndexChange;
but, if i want to add eventhandler at webForm, like:
<uc1:MyControl ID="MyControl1" runat="server"
SelectedIndexChanged="OnSelectedIndexChange" />
it will genarel a compile error : cannot create an object of type
'System.EventHandler' from string. How can I do that?
thanks,
Detail as blow:
-----------------------
MyControl.ascx
-----------------------
<%@ Control Language="C#" ClassName="MyControl" %>
<script runat="server">
public EventHandler SelectedIndexChanged;
public string SelectedValue
{
get
{
if (DropDownList1.SelectedIndex < 0)
return "";
else
return DropDownList1.SelectedValue;
}
}
protected void DropDownList1_SelectedIndexChanged(object sender,
EventArgs e)
{
if (SelectedIndexChanged != null)
SelectedIndexChanged(this, null);
}
</script>
<aspropDownList ID="DropDownList1" runat="server"
OnSelectedIndexChanged="DropDownList1_SelectedIndexChanged"
AutoPostBack=true>
<asp:ListItem Value=1 Text="item 01"></asp:ListItem>
<asp:ListItem Value=2 Text="item 02"></asp:ListItem>
<asp:ListItem Value=3 Text="item 03"></asp:ListItem>
</aspropDownList>
-----------------------------
MyTestControl.aspx
-----------------------------
<%@ Page Language="C#" %>
<%@ Register Src="Controls/MyControl.ascx" TagName="MyControl"
TagPrefix="uc1" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
void Page_Load(object sender, EventArgs e)
{
//MyControl1.SelectedIndexChanged = this.OnSelectedIndexChange;
}
void OnSelectedIndexChange(object sender, EventArgs e)
{
Label1.Text = "My selection is: " + MyControl1.SelectedValue;
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>My Control</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<uc1:MyControl ID="MyControl1" runat="server"
SelectedIndexChanged="OnSelectedIndexChange"
/> <hr />
<asp:Label ID="Label1" runat="server" Text=""></asp:Label>
</div>
</form>
</body>
</html>
Is there any way to add eventhandler to custom usercontrol and could
set it at webForm?
i can add eventhandler on code, such as at Page_Load, add:
MyControl1.SelectedIndexChanged = this.OnSelectedIndexChange;
but, if i want to add eventhandler at webForm, like:
<uc1:MyControl ID="MyControl1" runat="server"
SelectedIndexChanged="OnSelectedIndexChange" />
it will genarel a compile error : cannot create an object of type
'System.EventHandler' from string. How can I do that?
thanks,
Detail as blow:
-----------------------
MyControl.ascx
-----------------------
<%@ Control Language="C#" ClassName="MyControl" %>
<script runat="server">
public EventHandler SelectedIndexChanged;
public string SelectedValue
{
get
{
if (DropDownList1.SelectedIndex < 0)
return "";
else
return DropDownList1.SelectedValue;
}
}
protected void DropDownList1_SelectedIndexChanged(object sender,
EventArgs e)
{
if (SelectedIndexChanged != null)
SelectedIndexChanged(this, null);
}
</script>
<aspropDownList ID="DropDownList1" runat="server"
OnSelectedIndexChanged="DropDownList1_SelectedIndexChanged"
AutoPostBack=true>
<asp:ListItem Value=1 Text="item 01"></asp:ListItem>
<asp:ListItem Value=2 Text="item 02"></asp:ListItem>
<asp:ListItem Value=3 Text="item 03"></asp:ListItem>
</aspropDownList>
-----------------------------
MyTestControl.aspx
-----------------------------
<%@ Page Language="C#" %>
<%@ Register Src="Controls/MyControl.ascx" TagName="MyControl"
TagPrefix="uc1" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
void Page_Load(object sender, EventArgs e)
{
//MyControl1.SelectedIndexChanged = this.OnSelectedIndexChange;
}
void OnSelectedIndexChange(object sender, EventArgs e)
{
Label1.Text = "My selection is: " + MyControl1.SelectedValue;
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>My Control</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<uc1:MyControl ID="MyControl1" runat="server"
SelectedIndexChanged="OnSelectedIndexChange"
/> <hr />
<asp:Label ID="Label1" runat="server" Text=""></asp:Label>
</div>
</form>
</body>
</html>