Server.execute in asp.net - Part 54

Suggested Videos
Part 51 - Different page navigation techniques
Part 52 - Response.Redirect in asp.net
Part 53 - Server.Transfer in asp.net

The following are the different page navigation techniques in asp.net
1. Hyperlink control - Discussed in Part 13 and Part 51 of the ASP.NET video series
2. Response.Redirect - Discussed in Part 52
3. Server.Transfer - Discussed in Part 53
4. Server.Execute
5. Cross-Page postback
6. Window.Open 



In this video we will discuss about 
1. Server.Execute method
2. Difference between Server.Transfer and Server.Execute

Server.Transfer and Server.Execute are similar in many ways.
1. The URL in the browser remains the first page URL.
2. Server.Transfer and Server.Execute can only be used to navigate to sites/pages on the same web server. Trying to navigate to sites/pages on a different web server, causes runtime exception.
3. Server.Transfer and Server.Execute preserves the Form Variables from the original request.

The major difference between Server.Transfer and Server.Execute is that, Server.Transfer terminates the execution of the current page and starts the execution of the new page, where as Server.Execute process the second Web form without leaving the first Web form. After completing the execution of the first webform, the control returns to the second webform.



WebForm1.aspx code:
<div style="font-family: Arial">
    <table>
        <tr>
            <td colspan="2">
                <h1>
                    This is WebForm1</h1>
            </td>
        </tr>
        <tr>
            <td>
                <b>Name</b>
            </td>
            <td>
                :<asp:TextBox ID="txtName" runat="server">
                </asp:TextBox>
            </td>
        </tr>
        <tr>
            <td>
                <b>Email</b>
            </td>
            <td>
                :<asp:TextBox ID="txtEmail" runat="server">
                </asp:TextBox>
            </td>
        </tr>
        <tr>
            <td colspan="2">
                <asp:Button ID="btnExecute" runat="server" 
                Text="Server.Execute - WebForm2" 
                Width="250px" onclick="btnExecute_Click"/>
            </td>
        </tr>
        <tr>
            <td colspan="2">
                <asp:Button ID="btnExecuteToExternalWebsite" 
                runat="server" Width="250px" 
                Text="Server.Execute - External WebSite" 
                onclick="btnExecuteToExternalWebsite_Click" />
            </td>
        </tr>
        <tr>
            <td colspan="2">
                <asp:Label ID="lblStatus" ForeColor="Green" 
                Font-Bold="true" runat="server"></asp:Label>
            </td>
        </tr>
    </table>
</div>

WebForm1.aspx.cs code:
protected void btnExecute_Click(object sender, EventArgs e)
{
    Server.Execute("~/WebForm2.aspx", true);
    lblStatus.Text = "The call returned after processing the second webform";
}
protected void btnExecuteToExternalWebsite_Click(object sender, EventArgs e)
{
    Server.Execute("http://pragimtech.com/home.aspx");
}

WebForm2.aspx code:
<div style="font-family: Arial">
    <table>
        <tr>
            <td colspan="2">
                <h1>This is WebForm2</h1>
            </td>
        </tr>
        <tr>
            <td>
                <b>Name</b>
            </td>
            <td>
                :<asp:Label ID="lblName" runat="server">
                </asp:Label>
            </td>
        </tr>
        <tr>
            <td>
                <b>Email</b>
            </td>
            <td>
                :<asp:Label ID="lblEmail" runat="server">
                </asp:Label>
            </td>
        </tr>
        <tr>
            <td colspan="2">
                <asp:Button ID="btnPostBack" runat="server" 
                Text="Simply Post Back" />
            </td>
        </tr>
    </table>
</div>

WebForm2.aspx.cs code:
protected void Page_Load(object sender, EventArgs e)
{
    System.Collections.Specialized.NameValueCollection previousFormcollection = Request.Form;
    lblName.Text = previousFormcollection["txtName"];
    lblEmail.Text = previousFormcollection["txtEmail"];

    //Page previousPage = Page.PreviousPage;
    //if (previousPage != null)
    //{
    //    lblName.Text = ((TextBox)previousPage.FindControl("txtName")).Text;
    //    lblEmail.Text = ((TextBox)previousPage.FindControl("txtEmail")).Text;
    //}
}