Server side confirmation using javascript and VB

Question

1.00/5 (1 vote)

See more:

If i click yes its returns No

It return First click value on my second click ,

if i click yes first time it returns no,and i click second time no its return my first value yes..

What I have tried:

JavaScript

function Confirm() {
             var confirm_value = document.createElement("INPUT");
             confirm_value.type = "hidden";
             confirm_value.name = "confirm_value";
             if (confirm("Do you want to Delete data?")) {
                 confirm_value.value = "Yes";
             } else {
                 confirm_value.value = "No";
             }
             document.forms[0].appendChild(confirm_value);
         }

VB CODE

VB

System.Web.UI.ScriptManager.RegisterClientScriptBlock(Page, GetType(Page), "Script", "Confirm();", True)

        Dim confirmValue As String = Request.Form("confirm_value")
        If confirmValue = "Yes" Then

            Response.Write("User Clicked yes")
        Else
            Response.Write("User Clicked No")
        End If

Posted 2-Mar-17 2:39am

ManiLancer

Updated 2-Mar-17 4:22am

Bryian Tan

v2

Add a Solution

3 solutions

Solution 2

The approach here is wrong. If you want to confirm that a user is doing something then do something like this in JavaScript:

JavaScript

function ConfirmDelete(){
return confirm("Do you want to Delete data?"); // this means that the function will either return true or false depending on what user clicks.
}

Then in the ASPX side on your button you do this:

HTML

<aspButton id="btnConfirm" Text="Confirm" OnClientClick="return ConfirmDelete();" OnClick="btnClick" />

By adding OnClientClick to your button and then returning the value from ConfirmDelete(), if the user clicks Cancel in the Confirm dialog box, a false will be returned and OnClientClick will return false which will prevent the button from firing the postback and server side code. If user clicks OK in Confirm dialog then true is returned and the server side code will get executed.

Posted 2-Mar-17 2:50am

ZurdoDev

Comments

Karthik_Mahalingam 2-Mar-17 11:03am

5

Solution 1

It's hard to answer as we don't know the context the VB code is executed in. Is it in Page Load? Or somewhere else?

Your issue probably stems from a misunderstanding that RegisterClientScriptBlock is somehow running your javascript in code behind and that your .net code is running inside the browser and waits for your input and then does your "if" line after you click the confirmation in the browser. Well none of that is happening.

What RegisterClientScriptBlock is doing is adding that javascript to the output so that when all of your .net code has executed and all html has been built, that html is then sent to the browser and it is then that the javascript runs.

VB.NET

System.Web.UI.ScriptManager.RegisterClientScriptBlock(Page, GetType(Page), "Script", "Confirm();", True)
' after executing the line above your .net code continues running

Dim confirmValue As String = Request.Form("confirm_value")

' there is no confirm_value in the request so confirmValue will be ""

If confirmValue = "Yes" Then

Response.Write("User Clicked yes")
Else
Response.Write("User Clicked No")
End If

' now that your .net code has finished building html to send to the client, that
' html is sent and the browser then runs your js and the confirm box appears

Posted 2-Mar-17 2:50am

F-ES Sitecore

Comments

ManiLancer 2-Mar-17 9:41am

i want to run it in button click event , OnClientClick="return Confirm()" Wont work for my scenario,i want to call the function from code behind only

ZurdoDev 2-Mar-17 11:29am

OnClientClick is the right way to do it. Why won't it work for you?

ManiLancer 2-Mar-17 11:41am

ya right but i want it to cal it using code behind..

F-ES Sitecore 2-Mar-17 11:43am

Call what?

ManiLancer 2-Mar-17 11:45am

Javascript Function "Confirm()"

ManiLancer 2-Mar-17 11:46am

i submitted my solution ,its working fine

F-ES Sitecore 2-Mar-17 11:57am

You can't call javascript from server-side code. Server-side code is .net and it runs on the server, that code generates html (with embedded javascript in this case) and once all the .net code has finished running the html is handed to the browser and the js is executed in the browser.

ZurdoDev 2-Mar-17 11:51am

But why?

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

ManiLancer · Accepted Answer · 2017-03-02T04:22:00

This code Working Fine

JavaScript

function Confirm() {
    var confirm_value = document.createElement("INPUT");
    confirm_value.type = "hidden";
    confirm_value.name = "confirm_value";
    if (confirm("Do you want to Delete data?")) {
        confirm_value.value = "Yes";
    } else {
        confirm_value.value = "No";
    }
    document.forms[0].appendChild(confirm_value);
}

ASP.NET

<asp:Button ID="Button1" OnClientClick="Confirm()" runat="server"  Text="Button"/>

VB

Protected Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
       
    Button1.OnClientClick = "return Confirm();"

    Dim confirmValue As String
    confirmValue = Request.Form("confirm_value")

    If confirmValue = "Yes" Then
        Response.Write("User Clicked yes")
    Else
        Response.Write("User Clicked No")
    End If

End Sub