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)> _
PublicClass SmallGridWebPart
Inherits WebPart
Private connString AsString
' Use predefined strings for commands in the data source.PrivateConst selectStmt AsString = "Select * from [Customers]"PrivateConst deleteCmd AsString = "DELETE FROM [Customers] " _
& "WHERE [CustomerID] = @CustomerID"PrivateConst insertCmd AsString = "INSERT INTO [Customers] " _
& "([CustomerID], [CompanyName], [ContactName], [Phone]) " _
& "VALUES (@CustomerID, @CompanyName, @ContactName, @Phone)"PrivateConst updateCmd AsString = "UPDATE [Customers] SET " _
& "[CompanyName] = @CompanyName, [ContactName] = @ContactName, " _
& "[Phone] = @Phone WHERE [CustomerID] = @CustomerID"PublicSubNew()
ExportMode = WebPartExportMode.All
EndSub 'New
' This override prevents users from closing the control.PublicOverridesProperty AllowClose() AsBooleanGetReturnFalseEndGetSet(ByVal value AsBoolean)
' 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.EndSetEndProperty
' Allow page developers to set the connection string.PublicProperty ConnectionString() AsStringGetReturn connString
EndGetSet(ByVal value AsString)
connString = value
EndSetEndPropertyProtectedOverridesSub CreateChildControls()
Controls.Clear()
' Create the SqlDataSource control.Dim ds AsNew 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 AsNew ParameterCollection()
deleteParams.Add(BuildParam("CustomerID", TypeCode.String))
Dim insertParams AsNew 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 AsNew 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 AsNew GridView()
grid.ID = "customerGrid"
grid.Font.Size = 8
grid.AllowPaging = True
grid.AllowSorting = True
grid.AutoGenerateColumns = FalseDim fields AsString() = {"CustomerID"}
grid.DataKeyNames = fields
grid.DataSourceID = "dsCustomers"Dim controlButton AsNew 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)
EndSub 'CreateChildControls
PrivateFunction BuildParam(ByVal paramName AsString, _
ByVal dataTypeCode As TypeCode) As Parameter
Dim theParm AsNew Parameter(paramName, dataTypeCode)
Return theParm
EndFunction 'BuildParam
PrivateFunction BuildBoundField(ByVal fieldName _
AsString) As BoundField
Dim theField AsNew BoundField()
theField.DataField = fieldName
theField.HeaderText = fieldName
theField.SortExpression = fieldName
Return theField
EndFunction 'BuildBoundField
EndClass 'SmallGridWebPart
EndNamespace
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)]
publicclass SmallGridWebPart : WebPart
{
private String connString;
// Use predefined strings for commands in the data source.privateconststring selectStmt = @"Select * from [Customers]";
privateconststring deleteCmd = @"DELETE FROM [Customers] " +
@"WHERE [CustomerID] = @CustomerID";
privateconststring insertCmd = @"INSERT INTO [Customers] " +
@"([CustomerID], [CompanyName], [ContactName], " +
@"[Phone]) VALUES (@CustomerID, @CompanyName, " +
@"@ContactName, @Phone)";
privateconststring 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.publicoverridebool AllowClose
{
get
{
returnfalse;
}
// 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; }
}
protectedoverridevoid 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