Asp.net Webform Display Alert and redirect

I’m currently stuck. I have a webform with a button that registers or saves a record.
What i’d like to is have it display a javascript alert and then redirect to a page.
Here is the code i am using

protected void Save(..)
{   
    // Do save stuff
    DisplayAlert("The changes were saved Successfully");
    Response.Redirect("Default.aspx");
}

This code just redirects without giving the prompt Saved Successfully.

Here is my DisplayAlert Code

 protected virtual void DisplayAlert(string message)
    {
        ClientScript.RegisterStartupScript(
                        this.GetType(),
                        Guid.NewGuid().ToString(),
                        string.Format("alert('{0}');", message.Replace("'", @"'").Replace("n", "\n").Replace("r", "\r")),
                        true
                    );
    }

Can anyone help me find a solution to this?

Thanks

Answers:

Thank you for visiting the Q&A section on Magenaut. Please note that all the answers may not help you solve the issue immediately. So please treat them as advisements. If you found the post helpful (or not), leave a comment & I’ll get back to you as soon as possible.

Method 1

You can’t do a Response.Redirect because your javascript alert will never get displayed. Better to have your javascript code actually do a windows.location.href='default.aspx' to do the redirection after the alert is displayed. Something like this:

protected virtual void DisplayAlert(string message)
{
    ClientScript.RegisterStartupScript(
      this.GetType(),
      Guid.NewGuid().ToString(),
      string.Format("alert('{0}');window.location.href = 'default.aspx'", 
        message.Replace("'", @"'").Replace("n", "\n").Replace("r", "\r")),
        true);
}

Method 2

The DisplayAlert method adds the client script to the currently executing page request. When you call Response.Redirect, ASP.NET issues a HTTP 301 redirect to the browser, therefore starting a new page request where the registered client script no longer exists.

Since your code is executing on the server-side, there is no way to display the alert client-side and perform the redirect.

Also, displaying a JavaScript alert box can be confusing to a user’s mental workflow, an inline message would be much more preferable. Perhaps you could add the message to the Session and display this on the Default.aspx page request.

protected void Save(..)
{   
    // Do save stuff
    Session["StatusMessage"] = "The changes were saved Successfully";
    Response.Redirect("Default.aspx");
}

Then in Default.aspx.cs code behind (or a common base page class so this can happen on any page, or even the master page):

protected void Page_Load(object sender, EventArgs e)
{
    if(!string.IsNullOrEmpty((string)Session["StatusMessage"]))
    {
        string message = (string)Session["StatusMessage"];
        // Clear the session variable
        Session["StatusMessage"] = null;
        // Enable some control to display the message (control is likely on the master page)
        Label messageLabel = (Label)FindControl("MessageLabel");
        messageLabel.Visible = true;
        messageLabel.Text = message;
    }
}

The code isn’t tested but should point you in the right direction

Method 3

This works perfect:

string url = "home.aspx";
ClientScript.RegisterStartupScript(this.GetType(), "callfunction", "alert('Saved Sucessfully.');window.location.href = '" + url + "';",true);

Method 4

protected void Save(..)
{       
    // Do save stuff    
    ShowMessageBox();  
} 

private void ShowMessageBox()
{        
    string sJavaScript = "<script language=javascript>n";        
    sJavaScript += "var agree;n";        
    sJavaScript += "agree = confirm('Do you want to continue?.');n";        
    sJavaScript += "if(agree)n";        
    sJavaScript += "window.location = "http://google.com";n";        
    sJavaScript += "</script>";      
    Response.Write(sJavaScript);
}

All methods was sourced from stackoverflow.com or stackexchange.com, is licensed under cc by-sa 2.5, cc by-sa 3.0 and cc by-sa 4.0