Data-bound Web Parts Control Example
The following code example shows how to create a custom data-bound control that inherits from the WebPart class and can be used in Web Parts applications. For details about how to build this control and use it in an ASP.NET application, see How to: Build and Run the Data-bound Web Parts Control Example.
Example
Code
Imports System
Imports System.Collections
Imports System.ComponentModel
Imports System.Drawing
Imports System.Security.Permissions
Imports System.Web
Imports System.Web.Configuration
Imports System.Data.Sql
Imports System.Web.UI
Imports System.Web.UI.WebControls
Imports System.Web.UI.WebControls.WebParts
Namespace Samples.AspNet.VB.Controls
<AspNetHostingPermission(SecurityAction.Demand, _
Level:=AspNetHostingPermissionLevel.Minimal)> _
<AspNetHostingPermission(SecurityAction.InheritanceDemand, _
Level:=AspNetHostingPermissionLevel.Minimal)> _
Public Class SmallGridWebPart
Inherits WebPart
Private connString As String
' Use predefined strings for commands in the data source.
Private Const selectStmt As String = "Select * from [Customers]"
Private Const deleteCmd As String = "DELETE FROM [Customers] " _
& "WHERE [CustomerID] = @CustomerID"
Private Const insertCmd As String = "INSERT INTO [Customers] " _
& "([CustomerID], [CompanyName], [ContactName], [Phone]) " _
& "VALUES (@CustomerID, @CompanyName, @ContactName, @Phone)"
Private Const updateCmd As String = "UPDATE [Customers] SET " _
& "[CompanyName] = @CompanyName, [ContactName] = @ContactName, " _
& "[Phone] = @Phone WHERE [CustomerID] = @CustomerID"
Public Sub New()
ExportMode = WebPartExportMode.All
End Sub 'New
' This override prevents users from closing the control.
Public Overrides Property AllowClose() As Boolean
Get
Return False
End Get
Set(ByVal value As Boolean)
' No implementation for the set accessor. We have to have
' it because the base property has it, but we want to
' prevent users from closing the control and developers
' from being able to update the property.
End Set
End Property
' Allow page developers to set the connection string.
Public Property ConnectionString() As String
Get
Return connString
End Get
Set(ByVal value As String)
connString = value
End Set
End Property
Protected Overrides Sub CreateChildControls()
Controls.Clear()
' Create the SqlDataSource control.
Dim ds As New SqlDataSource(Me.ConnectionString, selectStmt)
ds.ID = "dsCustomers"
ds.DataSourceMode = SqlDataSourceMode.DataSet
ds.InsertCommandType = SqlDataSourceCommandType.Text
ds.InsertCommand = insertCmd
ds.UpdateCommandType = SqlDataSourceCommandType.Text
ds.UpdateCommand = updateCmd
ds.DeleteCommandType = SqlDataSourceCommandType.Text
ds.DeleteCommand = deleteCmd
Dim deleteParams As New ParameterCollection()
deleteParams.Add(BuildParam("CustomerID", TypeCode.String))
Dim insertParams As New ParameterCollection()
insertParams.Add(BuildParam("CustomerID", TypeCode.String))
insertParams.Add(BuildParam("CompanyName", TypeCode.String))
insertParams.Add(BuildParam("ContactName", TypeCode.String))
insertParams.Add(BuildParam("Phone", TypeCode.String))
Dim updateParams As New ParameterCollection()
updateParams.Add(BuildParam("CustomerID", TypeCode.String))
updateParams.Add(BuildParam("CompanyName", TypeCode.String))
updateParams.Add(BuildParam("ContactName", TypeCode.String))
updateParams.Add(BuildParam("Phone", TypeCode.String))
Me.Controls.Add(ds)
' Create the GridView control and bind it to the SqlDataSource.
Dim grid As New GridView()
grid.ID = "customerGrid"
grid.Font.Size = 8
grid.AllowPaging = True
grid.AllowSorting = True
grid.AutoGenerateColumns = False
Dim fields As String() = {"CustomerID"}
grid.DataKeyNames = fields
grid.DataSourceID = "dsCustomers"
Dim controlButton As New CommandField()
controlButton.ShowEditButton = True
controlButton.ShowSelectButton = True
grid.Columns.Add(controlButton)
Dim customerID As BoundField = BuildBoundField("CustomerID")
customerID.ReadOnly = True
grid.Columns.Add(customerID)
grid.Columns.Add(BuildBoundField("CompanyName"))
grid.Columns.Add(BuildBoundField("ContactName"))
grid.Columns.Add(BuildBoundField("Phone"))
Me.Controls.Add(grid)
End Sub 'CreateChildControls
Private Function BuildParam(ByVal paramName As String, _
ByVal dataTypeCode As TypeCode) As Parameter
Dim theParm As New Parameter(paramName, dataTypeCode)
Return theParm
End Function 'BuildParam
Private Function BuildBoundField(ByVal fieldName _
As String) As BoundField
Dim theField As New BoundField()
theField.DataField = fieldName
theField.HeaderText = fieldName
theField.SortExpression = fieldName
Return theField
End Function 'BuildBoundField
End Class 'SmallGridWebPart
End Namespace
using System;
using System.Collections;
using System.ComponentModel;
using System.Drawing;
using System.Security.Permissions;
using System.Web;
using System.Web.Configuration;
using System.Data.Sql;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
namespace Samples.AspNet.CS.Controls
{
[AspNetHostingPermission(SecurityAction.Demand,
Level = AspNetHostingPermissionLevel.Minimal)]
[AspNetHostingPermission(SecurityAction.InheritanceDemand,
Level = AspNetHostingPermissionLevel.Minimal)]
public class SmallGridWebPart : WebPart
{
private String connString;
// Use predefined strings for commands in the data source.
private const string selectStmt = @"Select * from [Customers]";
private const string deleteCmd = @"DELETE FROM [Customers] " +
@"WHERE [CustomerID] = @CustomerID";
private const string insertCmd = @"INSERT INTO [Customers] " +
@"([CustomerID], [CompanyName], [ContactName], " +
@"[Phone]) VALUES (@CustomerID, @CompanyName, " +
@"@ContactName, @Phone)";
private const string updateCmd = @"UPDATE [Customers] SET " +
@"[CompanyName] = @CompanyName, [ContactName] = @ContactName, " +
@"[Phone] = @Phone WHERE [CustomerID] = @CustomerID";
public SmallGridWebPart()
{
ExportMode = WebPartExportMode.All;
}
// This override prevents users from closing the control.
public override bool AllowClose
{
get
{
return false;
}
// No implementation for the set accessor. We have to have
// it because the base property has it, but we want to
// prevent users from closing the control and developers
// from being able to update the property.
set { ; }
}
// Allow page developers to set the connection string.
public String ConnectionString
{
get { return connString; }
set { connString = value; }
}
protected override void CreateChildControls()
{
Controls.Clear();
// Create the SqlDataSource control.
SqlDataSource ds = new SqlDataSource(this.ConnectionString, selectStmt);
ds.ID = "dsCustomers";
ds.DataSourceMode = SqlDataSourceMode.DataSet;
ds.InsertCommandType = SqlDataSourceCommandType.Text;
ds.InsertCommand = insertCmd;
ds.UpdateCommandType = SqlDataSourceCommandType.Text;
ds.UpdateCommand = updateCmd;
ds.DeleteCommandType = SqlDataSourceCommandType.Text;
ds.DeleteCommand = deleteCmd;
ParameterCollection deleteParams = new ParameterCollection();
deleteParams.Add(BuildParam("CustomerID", TypeCode.String));
ParameterCollection insertParams = new ParameterCollection();
insertParams.Add(BuildParam("CustomerID", TypeCode.String));
insertParams.Add(BuildParam("CompanyName", TypeCode.String));
insertParams.Add(BuildParam("ContactName", TypeCode.String));
insertParams.Add(BuildParam("Phone", TypeCode.String));
ParameterCollection updateParams = new ParameterCollection();
updateParams.Add(BuildParam("CustomerID", TypeCode.String));
updateParams.Add(BuildParam("CompanyName", TypeCode.String));
updateParams.Add(BuildParam("ContactName", TypeCode.String));
updateParams.Add(BuildParam("Phone", TypeCode.String));
this.Controls.Add(ds);
// Create the GridView control and bind it to the SqlDataSource.
GridView grid = new GridView();
grid.ID = "customerGrid";
grid.Font.Size = 8;
grid.AllowPaging = true;
grid.AllowSorting = true;
grid.AutoGenerateColumns = false;
String[] fields = { "CustomerID" };
grid.DataKeyNames = fields;
grid.DataSourceID = "dsCustomers";
CommandField controlButton = new CommandField();
controlButton.ShowEditButton = true;
controlButton.ShowSelectButton = true;
grid.Columns.Add(controlButton);
BoundField customerID = BuildBoundField("CustomerID");
customerID.ReadOnly = true;
grid.Columns.Add(customerID);
grid.Columns.Add(BuildBoundField("CompanyName"));
grid.Columns.Add(BuildBoundField("ContactName"));
grid.Columns.Add(BuildBoundField("Phone"));
this.Controls.Add(grid);
}
private Parameter BuildParam(String paramName, TypeCode dataTypeCode)
{
Parameter theParm = new Parameter(paramName, dataTypeCode);
return theParm;
}
private BoundField BuildBoundField(String fieldName)
{
BoundField theField = new BoundField();
theField.DataField = fieldName;
theField.HeaderText = fieldName;
theField.SortExpression = fieldName;
return theField;
}
}
}
See Also
Tasks
How to: Build and Run the Data-bound Web Parts Control Example
Concepts
Creating a Data-bound Web Parts Control