How to implement a C# custom server control?
I am trying to implement a custom control using a RowClickableGridView
class provided on this Stack Overflow post. This is the first time I h开发者_JAVA技巧ave tried to create a custom server control and followed steps laid out in this MSDN walkthrough.
I have the RowClickableGridView
class in the App\_Code
directory of my Web Application Project with a namespace of MyWebApplication.App\_Code
, and it compiles.
My problem is that the .aspx
page that I am trying to use the control on does not recognize the tag prefix. The page also has numerous warnings for unsupported elements between the cc1:GridViewRowClickable
tags. I thought I had everything in place according to the MSDN walkthrough.
Code Snippet
<%@ Page Title="MyPage" Language="C#" MasterPageFile="~/MyMaster.master" AutoEventWireup="true" Inherits="MyPage" Codebehind="MyPage.aspx.cs" %>
<%@ Register TagPrefix="cc1" TagName="RowClickableGridView" Namespace="MyWebApplication.App_Code" %>
<asp:Content ID="Content1" ContentPlaceHolderID="ContentPlaceHolder1" runat="Server">
<asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:MyConnectionString %>" SelectCommand="MySpName" SelectCommandType="StoredProcedure">
</asp:SqlDataSource>
<cc1:RowClickableGridView ID="GVW_test" runat="server" DataSourceID="SqlDataSource1">
<HeaderStyle CssClass="ListTop" />
<RowStyle CssClass="RowHighlight" />
<Columns>
<asp:BoundField HeaderText="ID" DataField="Atr_ID" SortExpression="Atr_ID" />
<asp:BoundField HeaderText="Name" DataField="Atr_Name" SortExpression="Atr_Name" />
</Columns>
<EmptyDataTemplate>
No Data
</EmptyDataTemplate>
</cc1:RowClickableGridView>
</asp:Content>
Any idea on what I am doing wrong or suggestions on what to try next?
You have specified "RowClickableGridView" as the TagName but you are using "GridViewRowClickable" in the code.
I got it to work finally. I took a different approach though.
- Create a new ASP.NET Server Control Project
- Copy class into default cs file and renamed namespace.
- Add default TagPrefix to line above namespace declaration.
[assembly: TagPrefix("mynamespace", "mycustomtag")]
- Add ToolBoxData to line above class copied.
[ToolboxData("<{0}:GridViewRowClickable runat=server></{0}:GridViewRowClickable>")]
- Build project into dll
- Copy dll to bin directory of Web Application
- Reference dll in Web Application Project
- Add controls to toolbox by adding creating a new toolbox item from the dll
- Drag and drop control from toolbox into aspx page
This adds the appropriate Register directive at the top of the aspx page and fixed all the warnings I received. The auto complete also works in this case as well.
Below is the code.
<%@ Page Title="" Language="C#" MasterPageFile="~/MyMaster.master" AutoEventWireup="true" Inherits="MyPage" Codebehind="MyPage.aspx.cs" %>
<%@ Register Assembly="GridViewRowClickable" Namespace="CustomServerControls" TagPrefix="MyTag" %>
<asp:Content ID="Content1" ContentPlaceHolderID="ContentPlaceHolder1" runat="Server">
<asp:SqlDataSource ID="Sql_MyTable" runat="server" ConnectionString="<%$ ConnectionStrings:MyConnectionString %>"
SelectCommand="spTbl_Select" SelectCommandType="StoredProcedure">
</asp:SqlDataSource>
<egcc:GridViewRowClickable ID="GridViewRowClickable_test" runat="server"
DataSourceID="Sql_MyTable" DataKeyNames="tbl_id"
AllowSorting="True" AutoGenerateColumns="False" GridLines="None" PageSize="25" Width="100%"
EnableRowClickSelection="true" RowClickCommand="Select" OnSelectedIndexChanged="GridViewRowClickable_test_OnSelectedIndexChanged">
<Columns>
<asp:BoundField HeaderText="ID" DataField="tbl_id" SortExpression="tbl_id" />
<asp:BoundField HeaderText="Name" DataField="tbl_name" SortExpression="tbl_name" />
</Columns>
<EmptyDataTemplate>
No Data.
</EmptyDataTemplate>
</egcc:GridViewRowClickable>
</asp:Content>
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