从一个C＃asp.net页到下一期的简单信息发布

Question

I am not using MVC but forms authentication. I am having trouble getting variable to store when the submit button is pressed. I have spend 2 days researching how to do this. At this point I am just trying to get the username to post on the next page. I truly thought I understood the way viewstate worked after doing this for a year.

Code:

protected void Page_Load(object sender, EventArgs e)
    {

        if (IsPostBack) {
            string username = Page.Session["username"].ToString();
            Response.Write(username);
        }

    }

    protected void btnSubmit_Click(object sender, EventArgs e)
    {
        Page.Session["username"] = txtUsername.Text;
    }

Answer 1

So after some searching I found the issue. Your code is valid, however, the postback happens BEFORE your Page.Session["username"] = txtUsername.Text; which means that if you sat there and clicked the button again, you should see the results.

I was hesitant to post this until I figured out a way to fix it (because who cares why you're having a problem if there is no solution) and I figured it out. You need to change the "UseSubmitBehavior" to false for the button. So your Page_Load would look like this:

protected void Page_Load(object sender, EventArgs e)
{
    if(IsPostBack) {
        string username = Page.Session["username"] as string; // will be null if empty
        Resopnse.Write(username);
    }
    btnSubmit.UseSubmitBehavior = false;
}

That should allow the value in txtUsername to be put into the Session variable before the postback and thus you will have access to it in the page load.