How to Print in ASP.NET 2.0

One of the most common functionality in any ASP.NET application is to print forms and controls. There are a lot of options to print forms using client scripts. In the article, we will see how to print controls in ASP.NET 2.0 using both server side code and javascript.

Step 1: Create a PrintHelper class. This class contains a method called PrintWebControl that can print any control like a GridView, DataGrid, Panel, TextBox etc. The class makes a call to window.print() that simulates the print button.

using System;

using System.Data;

using System.Configuration;

using System.Web;

using System.Web.Security;

using System.Web.UI;

using System.Web.UI.WebControls;

using System.Web.UI.WebControls.WebParts;

using System.Web.UI.HtmlControls;

using System.IO;

using System.Text;

using System.Web.SessionState;

public class PrintHelper

{

    public PrintHelper()

    {

    }

    public static void PrintWebControl(Control ctrl)

    {

        PrintWebControl(ctrl, string.Empty);

    }

    public static void PrintWebControl(Control ctrl, string Script)

    {

        StringWriter stringWrite = new StringWriter();

        System.Web.UI.HtmlTextWriter htmlWrite = new System.Web.UI.HtmlTextWriter(stringWrite);

        if (ctrl is WebControl)

        {

        Unit w = new Unit(100, UnitType.Percentage); ((WebControl)ctrl).Width = w;

        }

        Page pg = new Page();

        pg.EnableEventValidation = false;

        if (Script != string.Empty)

        {

        pg.ClientScript.RegisterStartupScript(pg.GetType(),"PrintJavaScript", Script);

        }

        HtmlForm frm = new HtmlForm();

        pg.Controls.Add(frm);

        frm.Attributes.Add("runat", "server");

        frm.Controls.Add(ctrl);

        pg.DesignerInitialize();

        pg.RenderControl(htmlWrite);

        string strHTML = stringWrite.ToString();

        HttpContext.Current.Response.Clear();

        HttpContext.Current.Response.Write(strHTML);

        HttpContext.Current.Response.Write("");

        HttpContext.Current.Response.End();

    }

}

Step 2: Create two pages, Default.aspx and Print.aspx. Default.aspx will contain the controls to be printed. Print.aspx will act as a popup page to invoke the print functionality.

Step 3: In your Default.aspx, drag and drop a few controls that you would like to print. To print a group of controls, place them all in a container control like a panel. This way if we print the panel using our PrintHelper class, all the controls inside the panel gets printed.

Step 4: Add a print button to the Default.aspx and in the code behind, type the following code:

protected void btnPrint_Click(object sender, EventArgs e)

    {

        Session["ctrl"] = Panel1;

        ClientScript.RegisterStartupScript(this.GetType(), "onclick", "");

    }

The code stores the control in a Session variable to be accessed in the pop up page, Print.aspx. If you want to print directly on button click, call the Print functionality in the following manner :

PrintHelper.PrintWebControl(Panel1);

Step 5: In the Page_Load event of Print.aspx.cs, add the following code:

protected void Page_Load(object sender, EventArgs e)

    {

        Control ctrl = (Control)Session["ctrl"];

        PrintHelper.PrintWebControl(ctrl);

    }