Question

When clicking the button for first time change button text, on 2nd click redirects to other page –

public partial class _Default : System.Web.UI.Page
{
    int clickCount;
    protected void btn_clicked(object sender, EventArgs e)
    {
        clickCount++;
        if (clickCount == 1)
            (sender as Button).Text = "go to landing page";
        else
            Response.Redirect("LandingPage.aspx");
    }
}

As obvious every time page reloads clickCount will be re-initialized and else block is never going to execute.
To maintain the clickCount state I may use view state, session state, application state, hidden field or JS code may be etc. What is best for this particular case -> Ques 1.

As MVC is stateless and similar code written in controller as well, will re-initlialize clickCount every time ActionHandler or controller is instantiated. How do you handle similar situation in ASP.NET MVC -> Ques. 2

Answer 1

Create a model to pass into the view with the property on it:

public int ClickCount{get;set;}

Then in the view, create a hidden value

@Html.HiddenFor(f=>f.ClickCount)

During the post event on the controller, update the model

public ActionResult(ViewModel model){
model.ClickCount++;
}