Microsoft .NET Blog: February 2015

Server Side Validation of CheckboxList in ASP.NET & C#

We can Validate CheckboxList using the CustomValidator on Client side and server-side as well.

Our approach here will be validating the checkboxlist on server-side.

1. Add the CheckboxList with some items as below.

<asp:CheckBoxList ID="CheckBoxList1" runat="server">
<asp:ListItem>A</asp:ListItem>
<asp:ListItem>B</asp:ListItem>
<asp:ListItem>C</asp:ListItem>
</asp:CheckBoxList>

2. Add a CustomValidator Control from the toolbox.

I have added a OnServerValidate event which will validate the checkboxlist on server side on button click.

<asp:CustomValidator ID="CustomValidator1" runat="server" ErrorMessage="Please select alteast one option" OnServerValidate="CustomValidator1_ServerValidate" ></asp:CustomValidator>

3. Add a Button to Check the Validations are working.

<asp:Button ID="Button1" runat="server" Text="Button" />

4. the c# code for validating the list.

protected void CustomValidator1_ServerValidate(object source, ServerValidateEventArgs args)
{
int count = 0;
foreach (ListItem item in CheckBoxList1.Items)
{
if (item.Selected)
{
count++;
break;
}
}

if (count > 0)
args.IsValid = true;
else
args.IsValid = false;

}

Validate CheckboxList in ASP.NET on Client Side using Javascript

We can Validate CheckboxList using the CustomValidator on Client side and server-side as well.

Our approach here will be validating the checkboxlist on client-side.

1. Add the CheckboxList with some items as below.

<asp:CheckBoxList ID="CheckBoxList1" runat="server">
<asp:ListItem>A</asp:ListItem>
<asp:ListItem>B</asp:ListItem>
<asp:ListItem>C</asp:ListItem>
</asp:CheckBoxList>

2. Add a CustomValidator Control from the toolbox.

I have added a ClientValidateFunction which will be a javascript function ValidateCheckBoxList to validate.

<asp:CustomValidator ID="CustomValidator1" runat="server" ErrorMessage="Please select alt-east one option" ClientValidationFunction="ValidateCheckBoxList"></asp:CustomValidator>

3. Add a Button to Check the Validations are working.

<asp:Button ID="Button1" runat="server" Text="Button" />

4. Add the following java script to the Page which will validate the CheckBoxList.

<script type="text/javascript">
function ValidateCheckBoxList(source, args) {
var chkListModules = document.getElementById('<%= CheckBoxList1.ClientID %>');
var chkListinputs = chkListModules.getElementsByTagName("input");
for (var i = 0; i < chkListinputs.length; i++) {
if (chkListinputs[i].checked) {
args.IsValid = true;
return;
}
}
args.IsValid = false;
}

</script>

GridView Export To Word ASP.NET & C#

In this article we will see how to export grid-view to excel or word.

Step 1 : Create a new database in SQL server or if you have a database already go to step 2.

CREATE DATABASE (YOUR DATABASE NAME);

Step 2 : Create a table in the database.

CREATE TABLE Employee
(
EmployeeID INT,
Name Varchar(250),
Salary Decimal (10,2)

);

Step 3 : Insert some sample data to the table.

INSERT INTO Employee VALUES (1,'Scott',1000);
INSERT INTO Employee VALUES (2,'John',1100);
INSERT INTO Employee VALUES (3,'Phil',1200);
INSERT INTO Employee VALUES (4,'Peter',1300);
INSERT INTO Employee VALUES (5,'Jose',1400);

INSERT INTO Employee VALUES (6,'Morgan',1500);

Step 4 : Now Add a WebForm to your Project and add the GridView Control and Button to Export the Data.

<asp:GridView ID="GridView1" runat="server"></asp:GridView>

<asp:Button ID="btnExportWord" runat="server" Text="Export To Word" OnClick="btnExportWord_Click" />

Step 5 : Add the following code to your Page.

using System;

using System.Collections.Generic;

using System.Data;

using System.Data.SqlClient;

using System.IO;

using System.Linq;

using System.Web;

using System.Web.UI;

using System.Web.UI.WebControls;

protected void Page_Load(object sender, EventArgs e)

{

if (!IsPostBack)

{

BindGridView();

}

private void BindGridView()

{

string connectionString = "Data Source=.SQLEXPRESS;Initial Catalog=Employee;Integrated Security=True";

using (SqlConnection con = new SqlConnection(connectionString))

{

SqlCommand cmd = new SqlCommand();

cmd.CommandText = "SELECT * FROM Employee";

cmd.Connection = con;

con.Open();

SqlDataReader dr = cmd.ExecuteReader();

DataTable dt = new DataTable();

dt.Load(dr);

GridView1.DataSource = dt;

GridView1.DataBind();

}

private void ExportGridView(string fileName, string contentType)

{

Response.Clear();

Response.Buffer = true;

Response.AddHeader("content-disposition", "attachment;filename=" + fileName);

Response.Charset = "";

Response.ContentType = contentType;

StringWriter sw = new StringWriter();

HtmlTextWriter hw = new HtmlTextWriter(sw);

GridView1.RenderControl(hw);

Response.Output.Write(sw.ToString());

Response.Flush();

Response.Close();

Response.End();

}

protected void btnExportWord_Click(object sender, EventArgs e)
{
ExportGridView("GridData.doc", "application/vnd.ms-word");
}

public override void VerifyRenderingInServerForm(Control control)

{

}

GridView Export To Excel in ASP.NET & C#