Add and Remove HTML elements dynamically with Javascript

http://www.dustindiaz.com/add-and-remove-html-elements-dynamically-with-javascript/

Encrypt and Decrypt Connection String

http://www.dotnetspider.com/resources/2125-Encrypt-Decrypt-Connection-String.aspx

Make fancy buttons using CSS sliding doors technique

http://www.jankoatwarpspeed.com/post/2008/04/30/make-fancy-buttons-using-css-sliding-doors-technique.aspx

Nested GridView in ASP.NET

http://www.codeproject.com/KB/webforms/EditNestedGridView.aspx

Nested GridView in ASP.NET

http://www.codeproject.com/KB/webforms/EditNestedGridView.aspx

Microsoft Anti-Cross Site Scripting Library V1.5: Protecting the Contoso Bookmark Page

http://msdn.microsoft.com/en-us/library/aa973813.aspx

Export GridView To Word/Excel/PDF/CSV in ASP.Net

Export GridView To Word/Excel/PDF/CSV in ASP.Net

In this article, I will explain how to export GridView to Word, Excel, PDF and CSV formats.

Exporting to Word, Excel and CSV can be easily achieved using ASP.Net without any third party tools, but for exporting GridView to PDF I am using iTextSharp which is a free library for exporting html to PDF.


To start with I have a GridView in which I am showing Customers records from the NorthWind Database.

The HTML markup of the GridView is as shown below



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

AutoGenerateColumns = "false" Font-Names = "Arial"

Font-Size = "11pt" AlternatingRowStyle-BackColor = "#C2D69B"

HeaderStyle-BackColor = "green" AllowPaging ="true"

OnPageIndexChanging = "OnPaging" >

<Columns>

<asp:BoundField ItemStyle-Width = "150px" DataField = "CustomerID"

HeaderText = "CustomerID" />

<asp:BoundField ItemStyle-Width = "150px" DataField = "City"

HeaderText = "City"/>

<asp:BoundField ItemStyle-Width = "150px" DataField = "Country"

HeaderText = "Country"/>

<asp:BoundField ItemStyle-Width = "150px" DataField = "PostalCode"

HeaderText = "PostalCode"/>

</Columns>

</asp:GridView>



In the figure below the GridView is shown with four buttons

1. Export To Word

2. Export To Excel

3. Export To PDF

4. Export To CSV


GridView with Sample Data


Export to Microsoft Word Format



C#

protected void btnExportWord_Click(object sender, EventArgs e)

{

Response.Clear();

Response.Buffer = true;

Response.AddHeader("content-disposition",

"attachment;filename=GridViewExport.doc");

Response.Charset = "";

Response.ContentType = "application/vnd.ms-word ";

StringWriter sw= new StringWriter();

HtmlTextWriter hw = new HtmlTextWriter(sw);

GridView1.AllowPaging = false;

GridView1.DataBind();

GridView1.RenderControl(hw);

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

Response.Flush();

Response.End();

}



VB.Net

Protected Sub btnExportWord_Click(ByVal sender As Object,

ByVal e As EventArgs)

Response.Clear()

Response.Buffer = True

Response.AddHeader("content-disposition",

"attachment;filename=GridViewExport.doc")

Response.Charset = ""

Response.ContentType = "application/vnd.ms-word "

Dim sw As New StringWriter()

Dim hw As New HtmlTextWriter(sw)

GridView1.AllowPaging = False

GridView1.DataBind()

GridView1.RenderControl(hw)

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

Response.Flush()

Response.End()

End Sub



The above function renders the GridView contents as Microsoft Word format. You will notice I have disabled paging before exporting, so that all the pages are exported.

The Output Exported File


GridView data exported to Word Document


Export to Microsoft Excel Format



For exporting the document to Excel if you do it directly as done in case of word the row background color is applied throughout to all the columns in the Excel Sheet hence in order to avoid it. I have done a workaround below.

First I am changing the background color of each row back to white.

Then I am applying the background color to each individual cell rather than the whole row. Thus when you export now you will notice that the formatting is applied only to the GridView cells and not all

Also I am applying textmode style class to all cells and then adding the style CSS class to the GridView before rendering it, this ensures that all the contents of GridView are rendered as text.



protected void btnExportExcel_Click(object sender, EventArgs e)

{

Response.Clear();

Response.Buffer = true;



Response.AddHeader("content-disposition",

"attachment;filename=GridViewExport.xls");

Response.Charset = "";

Response.ContentType = "application/vnd.ms-excel";

StringWriter sw = new StringWriter();

HtmlTextWriter hw = new HtmlTextWriter(sw);



GridView1.AllowPaging = false;

GridView1.DataBind();



//Change the Header Row back to white color

GridView1.HeaderRow.Style.Add("background-color", "#FFFFFF");



//Apply style to Individual Cells

GridView1.HeaderRow.Cells[0].Style.Add("background-color", "green");

GridView1.HeaderRow.Cells[1].Style.Add("background-color", "green");

GridView1.HeaderRow.Cells[2].Style.Add("background-color", "green");

GridView1.HeaderRow.Cells[3].Style.Add("background-color", "green");



for (int i = 0; i < GridView1.Rows.Count;i++ )

{

GridViewRow row = GridView1.Rows[i];



//Change Color back to white

row.BackColor = System.Drawing.Color.White;



//Apply text style to each Row

row.Attributes.Add("class", "textmode");



//Apply style to Individual Cells of Alternating Row

if (i % 2 != 0)

{

row.Cells[0].Style.Add("background-color", "#C2D69B");

row.Cells[1].Style.Add("background-color", "#C2D69B");

row.Cells[2].Style.Add("background-color", "#C2D69B");

row.Cells[3].Style.Add("background-color", "#C2D69B");

}

}

GridView1.RenderControl(hw);



//style to format numbers to string

string style = @"<style> .textmode { mso-number-format:\@; } </style>";

Response.Write(style);

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

Response.Flush();

Response.End();

}





VB.Net



Protected Sub btnExportExcel_Click(ByVal sender As Object,

ByVal e As EventArgs)

Response.Clear()

Response.Buffer = True



Response.AddHeader("content-disposition",

"attachment;filename=GridViewExport.xls")

Response.Charset = ""

Response.ContentType = "application/vnd.ms-excel"



Dim sw As New StringWriter()

Dim hw As New HtmlTextWriter(sw)



GridView1.AllowPaging = False

GridView1.DataBind()



'Change the Header Row back to white color

GridView1.HeaderRow.Style.Add("background-color", "#FFFFFF")



'Apply style to Individual Cells

GridView1.HeaderRow.Cells(0).Style.Add("background-color", "green")

GridView1.HeaderRow.Cells(1).Style.Add("background-color", "green")

GridView1.HeaderRow.Cells(2).Style.Add("background-color", "green")

GridView1.HeaderRow.Cells(3).Style.Add("background-color", "green")



For i As Integer = 0 To GridView1.Rows.Count - 1

Dim row As GridViewRow = GridView1.Rows(i)



'Change Color back to white

row.BackColor = System.Drawing.Color.White



'Apply text style to each Row

row.Attributes.Add("class", "textmode")



'Apply style to Individual Cells of Alternating Row

If i Mod 2 <> 0 Then

row.Cells(0).Style.Add("background-color", "#C2D69B")

row.Cells(1).Style.Add("background-color", "#C2D69B")

row.Cells(2).Style.Add("background-color", "#C2D69B")

row.Cells(3).Style.Add("background-color", "#C2D69B")

End If

Next

GridView1.RenderControl(hw)



'style to format numbers to string

Dim style As String = "<style>.textmode{mso-number-format:\@;}</style>"

Response.Write(style)

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

Response.Flush()

Response.End()

End Sub



The Output Exported File


GridView data exported to Excel Document


Export to Portable Document Format



For exporting the GridView to PDF I am using the iTextSharp Library. You will need to Add Reference for the iTextSharp Library in your Website.

Then import the following Namespaces



C#

using iTextSharp.text;

using iTextSharp.text.pdf;

using iTextSharp.text.html;

using iTextSharp.text.html.simpleparser;



VB.Net

Imports iTextSharp.text

Imports iTextSharp.text.pdf

Imports iTextSharp.text.html

Imports iTextSharp.text.html.simpleparser



By default the iTextSharp Library does not support background color of table cells or table rows

Hence when you render it as PDF your GridView is rendered without any formatting.

Recently I read an article on hamang.net where the author has provided the snippet to modify the iTextSharp so that it exports the HTML with background color.



For this tutorial, I have already modified the iTextSharp Library DLL so that the GridView is rendered with all the background color used. You can refer the code for exporting GridView to PDF below




C#

protected void btnExportPDF_Click(object sender, EventArgs e)

{

Response.ContentType = "application/pdf";

Response.AddHeader("content-disposition",

"attachment;filename=GridViewExport.pdf");

Response.Cache.SetCacheability(HttpCacheability.NoCache);

StringWriter sw = new StringWriter();

HtmlTextWriter hw = new HtmlTextWriter(sw);

GridView1.AllowPaging = false;

GridView1.DataBind();

GridView1.RenderControl(hw);

StringReader sr = new StringReader(sw.ToString());

Document pdfDoc = new Document(PageSize.A4, 10f,10f,10f,0f);

HTMLWorker htmlparser = new HTMLWorker(pdfDoc);

PdfWriter.GetInstance(pdfDoc, Response.OutputStream);

pdfDoc.Open();

htmlparser.Parse(sr);

pdfDoc.Close();

Response.Write(pdfDoc);

Response.End();

}



VB.Net

Protected Sub btnExportPDF_Click(ByVal sender As Object,

ByVal e As EventArgs)

Response.ContentType = "application/pdf"

Response.AddHeader("content-disposition",

"attachment;filename=GridViewExport.pdf")

Response.Cache.SetCacheability(HttpCacheability.NoCache)

Dim sw As New StringWriter()

Dim hw As New HtmlTextWriter(sw)

GridView1.AllowPaging = False

GridView1.DataBind()

GridView1.RenderControl(hw)

Dim sr As New StringReader(sw.ToString())

Dim pdfDoc As New Document(PageSize.A4, 10.0F, 10.0F, 10.0F, 0.0F)

Dim htmlparser As New HTMLWorker(pdfDoc)

PdfWriter.GetInstance(pdfDoc, Response.OutputStream)

pdfDoc.Open()

htmlparser.Parse(sr)

pdfDoc.Close()

Response.Write(pdfDoc)

Response.End()

End Sub



The Output Exported File


GridView data exported to PDF Document


Export to Text/CSV



Finally comes exporting GridView to CSV or Text File delimited by a separator like comma.

To export the GridView as CSV, I am running a two for loops. While looping through the GridView columns and appending comma after each column and while looping through rows appending new line character. Refer the code below.



C#

protected void btnExportCSV_Click(object sender, EventArgs e)

{

Response.Clear();

Response.Buffer = true;

Response.AddHeader("content-disposition",

"attachment;filename=GridViewExport.csv");

Response.Charset = "";

Response.ContentType = "application/text";



GridView1.AllowPaging = false;

GridView1.DataBind();



StringBuilder sb = new StringBuilder();

for (int k = 0; k < GridView1.Columns.Count; k++)

{

//add separator

sb.Append(GridView1.Columns[k].HeaderText + ',');

}

//append new line

sb.Append("\r\n");

for (int i = 0; i < GridView1.Rows.Count; i++)

{

for (int k = 0; k < GridView1.Columns.Count; k++)

{

//add separator

sb.Append(GridView1.Rows[i].Cells[k].Text + ',');

}

//append new line

sb.Append("\r\n");

}

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

Response.Flush();

Response.End();

}




VB.Net

Protected Sub btnExportCSV_Click(ByVal sender As Object,

ByVal e As EventArgs)

Response.Clear()

Response.Buffer = True

Response.AddHeader("content-disposition",

"attachment;filename=GridViewExport.csv")

Response.Charset = ""

Response.ContentType = "application/text"



GridView1.AllowPaging = False

GridView1.DataBind()



Dim sb As New StringBuilder()

For k As Integer = 0 To GridView1.Columns.Count - 1

'add separator

sb.Append(GridView1.Columns(k).HeaderText + ","c)

Next

'append new line

sb.Append(vbCr & vbLf)

For i As Integer = 0 To GridView1.Rows.Count - 1

For k As Integer = 0 To GridView1.Columns.Count - 1

'add separator

sb.Append(GridView1.Rows(i).Cells(k).Text + ","c)

Next

'append new line

sb.Append(vbCr & vbLf)

Next

Response.Output.Write(sb.ToString())

Response.Flush()

Response.End()

End Sub



The Output Exported File


GridView data exported to CSV File


When you run the application first time and click export you might receive the following error


Error encountered when you click export


To avoid the error you will need to add this event which ensures that the GridView is Rendered before exporting.


C#

public override void VerifyRenderingInServerForm(Control control)

{

/* Verifies that the control is rendered */

}



VB.Net

Public Overloads Overrides Sub VerifyRenderingInServerForm

(ByVal control As Control)

' Verifies that the control is rendered

End Sub



This completes the article you can view the live demo here

The source code is available in C# and VB.Net here