ListView Control with LINQ to SQL Class

Home » Article » ASP.Net Article » ListView Control with LINQ to SQL Class– Part 2 Submit Articles and Win Geeky Prizes!!

You are not logged in.

	Search

	ASP.Net Web Hosting

	Product Spotlight

	Technologies
	ASP.Net C# ASP.Net AJAX IIS .NetFramework Webservices ADO Sql Server Reporting Services Directory Services Windows Clustering Javascript Sharepoint Services

	CodeDigest Navigation
	Home Register Login Article Guidelines Submit Article Submit Codes Support Us Admin

	Technology News
	No News Feeds available at this time.

	Community News
	Submit Code Snippet!! Not everyone can spend time for writing articles! But it is possible for most of to share a working code snippet!! Now you can post your code snippet to CodeDigest.Com. Join our community and post code snippets!!! Happy Coding!!!. Read more..

ListView Control with LINQ to SQL Class– Part 2

By Satheesh babu
Posted On Oct 06,2008

Article Rating: (Login)


Be first to rate this article.

No of Comments: 0

Category: ASP.Net 3.5


Print this article.

ListView Control with LINQ to SQL Class– Part 2

In Part1, we have seen the basics of LINQ to SQL classes and the tools (LINQ to SQL designer) for generating LINQ to SQL class in Visual Studio 2008. Also, we have binded ListView control with LINQ datasource controls and provided edit, update, delete and insert feature using LINQ data source control. In Part 2, we will understand how the same tasks can be done without LinqDataSource control. We will use the same Employee table to understand the custom databinding using LINQ.

Designing the LINQ to SQL classes

In solution explorer, right the project and select “Add New Item”. Select “LINQ to SQL classes” as shown in below figure. I have named it as EmployeeInfo.

$F:\Articles\Dot Net 3.5\LINQ to SQL\add.png$

This will add an EmployeeInfo.dbml file inside “App_Code” folder. In Visual Studio, EmployeeInfo.dbml will have 2 panes. The left pane is for deigning the data objects and the right pane can be used for creating methods that operates on the data objects.

Once we include the LINQ to SQL Class in the project, there will be 3 files added to the App_Code.

EmployeeInfo.dbml

Ø An XML file that contains information about the tables like table name, column name, type, etc

EmployeeInfo.layout

Ø An XML file that specifies how the designer places the objects.

EmployeeInfo.designer.cs

Ø The C# code file that will have code to interact with the underlying database called DataContext object. It also has entity class definition.

Open Server Explorer, Expand the database tables.

Drag Employee and Department into LINQ to SQL designer. The Objects will be created automatically. Refer the below figure.

$F:\Articles\Dot Net 3.5\LINQ to SQL\designer.png$

This will update the EmployeeInfo.designer.cs file with class definition for Employee and Department. It will also generate the DataContext object for these objects for interacting with the underlying datasource. In our case, it is EmployeeInfoDataContext class. Open the file EmployeeInfo.designer.cs and we can see the generated code for datasource interactions.

The arrow between the object is the foreign key relationship between them. This means that the Employee class will have the Department class as a member.

Thus, we have modelled LINQ to SQL classes which has O/R mapping. Moving forward, we will use these objects to bind a ListView control.

Binding the ListView

ListView is a new databound control that is shipped with ASP.Net 3.5. In short, ListView control can be thought as a hybrid between GridView and Repeater control which can be used to display data in any custom layout with inbuilt edit, update, and sort feature.

In Part 1, we have used LinqDataSource control to bind the ListView control. In Part 2, we will bind the ListView Control without LinqDataSource control using LINQ to SQL classes and provide edit, update and delete functionality to it by writing custom LINQ query.

Steps

1. Design the ListView control with LayoutTemplate, ItemTemplate, InsertItemTemplate, and EditItemTemplate. Refer the below code. We will have a dropdownlist for binding the list of available departments in InsertItemTemplate and EditItemTemplate.

<asp:ListView ID="lvEmployee" runat="server"

InsertItemPosition="LastItem" onitemcanceling="lvEmployee_ItemCanceling"

onitemediting="lvEmployee_ItemEditing"

onitemupdating="lvEmployee_ItemUpdating"

onitemdeleting="lvEmployee_ItemDeleting"

oniteminserting="lvEmployee_ItemInserting">

</th>

EmpID</th>

EmpName</th>

Department</th>

Age</th>

Address</th>

</tr>

</tr>

</table>

</td>

</tr>

</td>

</tr>

</table>

</LayoutTemplate>

<td>

<asp:Button ID="DeleteButton" runat="server" CommandName="Delete"

Text="Delete" />

<asp:Button ID="EditButton" runat="server" CommandName="Edit" Text="Edit" />

</td>

<td>

<asp:Label ID="EmpIDLabel" runat="server" Text='<%# Eval("EmpID") %>' />

</td>

<td>

<asp:Label ID="EmpNameLabel" runat="server" Text='<%# Eval("EmpName") %>' />

</td>

<td>

<asp:Label ID="DepartmentLabel" runat="server"

Text='<%# Eval("Department.DepartmentName") %>' />

</td>

<td>

<asp:Label ID="AgeLabel" runat="server" Text='<%# Eval("Age") %>' />

</td>

<td>

<asp:Label ID="AddressLabel" runat="server" Text='<%# Eval("Address") %>' />

</td>

</tr>

</ItemTemplate>

<td>

<asp:Button ID="UpdateButton" runat="server" CommandName="Update"

Text="Update" />

<asp:Button ID="CancelButton" runat="server" CommandName="Cancel"

Text="Cancel" />

</td>

<td>

<asp:Label ID="EmpIDLabel1" runat="server" Text='<%# Eval("EmpID") %>' />

</td>

<td>

<asp:TextBox ID="EmpNameTextBox" runat="server" Text='<%# Bind("EmpName") %>' />

</td>

<td>

<asp:DropDownList ID="DropDownList2" DataSource="<%# BindDept() %>"

SelectedValue='<%# Bind("DeptID") %>'

DataTextField="DepartmentName" DataValueField="DeptID" runat="server">

</asp:DropDownList>

</td>

<td>

<asp:TextBox ID="AgeTextBox" runat="server" Text='<%# Bind("Age") %>' />

</td>

<td>

<asp:TextBox ID="AddressTextBox" runat="server" Text='<%# Bind("Address") %>' />

</td>

</tr>

</EditItemTemplate>

<td>

<asp:Button ID="InsertButton" runat="server" CommandName="Insert"

Text="Insert" />

<asp:Button ID="CancelButton" runat="server" CommandName="Cancel"

Text="Clear" />

</td>

<td>

 </td>

<td>

<asp:TextBox ID="EmpNameTextBox" runat="server" />

</td>

<td>

<asp:DropDownList ID="DropDownList1"

DataTextField="DepartmentName" DataValueField="DeptID" runat="server">

</asp:DropDownList>

</td>

<td>

<asp:TextBox ID="AgeTextBox" runat="server" />

</td>

<td>

<asp:TextBox ID="AddressTextBox" runat="server" />

</td>

</tr>

</InsertItemTemplate>

</asp:ListView>

Similar Articles

Create Dynamic GridView Control in C#/ASP.Net

Posted on 11/19/2008 @ 8:09 AM By Satheesh Babu

Restrict Asp.Net Validator controls to Fire on Page Submit

Posted on 11/9/2008 @ 5:58 AM By Satheesh Babu

Creating Dynamic DataList control in C#/ASP.Net

Posted on 11/6/2008 @ 8:44 AM By Satheesh Babu

Plug & play architecture using policy application blocks

Posted on 10/20/2008 @ 7:38 AM By Shiv koi

ListView Control with LINQ to SQL Class– Part 2

Posted on 10/6/2008 @ 8:44 AM By Satheesh Babu

2. Bind the ListView from the CodeBehind using LINQ query and LINQ to SQL classes.

protected void Page_Load(object sender, EventArgs e)

{

if (!IsPostBack)

{

BindEmp();

//Dropdown in InsertItemtemplate

DropDownList ddl = lvEmployee.InsertItem.FindControl("DropDownList1") as DropDownList;

ddl.DataSource = BindDept();

ddl.DataBind();

}

public void BindEmp()

{

EmployeeInfoDataContext dbEmp = new EmployeeInfoDataContext();

var LINQQuery = from emp in dbEmp.Employees

select emp;

lvEmployee.DataSource = LINQQuery;

lvEmployee.DataBind();

}

public IEnumerable BindDept()

{

EmployeeInfoDataContext dbEmp = new EmployeeInfoDataContext();

var LINQQuery = from dept in dbEmp.Departments

select dept;

return LINQQuery as IEnumerable;

}

Execute the page; you can see ListView with employee records.

$F:\Articles\Dot Net 3.5\LINQ to SQL\LVWithcustomLINQ.png$

3. For ListView edit, delete and insert command to work we need to write custom LINQ query and execute it using LINQ to SQL classes. The custom LINQ queries are bolded in the below code.

protected void lvEmployee_ItemEditing(object sender, ListViewEditEventArgs e)

{

lvEmployee.EditIndex = e.NewEditIndex;

BindEmp();

}

protected void lvEmployee_ItemCanceling(object sender, ListViewCancelEventArgs e)

{

lvEmployee.EditIndex = -1;

BindEmp();

}

protected void lvEmployee_ItemUpdating(object sender, ListViewUpdateEventArgs e)

{

EmployeeInfoDataContext dbEmp = new EmployeeInfoDataContext();

Label lblTemp = lvEmployee.Items[e.ItemIndex].FindControl("EmpIDLabel1") as Label;

if(lblTemp !=null)

string EmpID = lblTemp.Text;

Employee empTemp = (from emp in dbEmp.Employees

where emp.EmpID == int.Parse(EmpID)

select emp).Single();

TextBox txtTemp = lvEmployee.Items[e.ItemIndex].FindControl("EmpNameTextBox") as TextBox;

if (txtTemp != null)

empTemp.EmpName = txtTemp.Text;

DropDownList ddlTemp = lvEmployee.Items[e.ItemIndex].FindControl("DropDownList2") as DropDownList;

if (txtTemp != null)

empTemp.DeptID = int.Parse(ddlTemp.SelectedValue);

txtTemp = lvEmployee.Items[e.ItemIndex].FindControl("AgeTextBox") as TextBox;

if (txtTemp != null)

empTemp.Age = int.Parse(txtTemp.Text);

txtTemp = lvEmployee.Items[e.ItemIndex].FindControl("AddressTextBox") as TextBox;

if (txtTemp != null)

empTemp.Address = txtTemp.Text;

dbEmp.SubmitChanges();

lvEmployee.EditIndex = -1;

BindEmp();

}

protected void lvEmployee_ItemDeleting(object sender, ListViewDeleteEventArgs e)

{

EmployeeInfoDataContext dbEmp = new EmployeeInfoDataContext();

Label lblTemp = lvEmployee.Items[e.ItemIndex].FindControl("EmpIDLabel") as Label;

if(lblTemp !=null)

string EmpID = lblTemp.Text;

Employee empTemp = (from emp in dbEmp.Employees

where emp.EmpID == int.Parse(EmpID)

select emp).Single();

dbEmp.Employees.DeleteOnSubmit(empTemp);

dbEmp.SubmitChanges();

BindEmp();

}

protected void lvEmployee_ItemInserting(object sender, ListViewInsertEventArgs e)

{

EmployeeInfoDataContext dbEmp = new EmployeeInfoDataContext();

Employee emp = new Employee();

TextBox txtTemp = e.Item.FindControl("EmpNameTextBox") as TextBox;

emp.EmpName = txtTemp.Text;

DropDownList ddlTemp = e.Item.FindControl("DropDownList1") as DropDownList;

emp.DeptID = int.Parse(ddlTemp.SelectedValue);

txtTemp = e.Item.FindControl("AgeTextBox") as TextBox;

emp.Age = int.Parse(txtTemp.Text);

txtTemp = e.Item.FindControl("AddressTextBox") as TextBox;

emp.Address = txtTemp.Text;

dbEmp.Employees.InsertOnSubmit(emp);

dbEmp.SubmitChanges();

BindEmp();

}

Execute the page and see ListView edit/update/delete/insert in action using LINQ.

Downloads

Source Code

Conclusion

In Part 1, we have understood the basics of LINQ to SQL and using it asp.net by binding ListView control by using LinqDataSource controls. The Part 2 of this article helped to write custom LINQ query to do see ListView edit/update/delete/insert using LINQ to SQL classes. Download the source attached with this article. Thanks for reading my article.

Happy Coding!!

Article Feedback

Title

Submitted By

Comment

Enter the verification number

Comments