Why is my Asp.Net Form arriving empty when I post from Page to Page?

问题

I have the following HTML Code

<%@ Page Language="C#" %>

<html>
    <head>
        <title></title>
    </head>
    <body>
        <form id="frmSystem" method="post" action="target.aspx">
            <input id="txtTextField" type="text" />
            <input id="btnPost" value="Submit" onclick="javascript:frmSystem.submit();" type="button" />
        </form>
    </body>
</html>

The target Page is coming up but the form that it is receiving is empty. I have a break point on my target.aspx page and while I can see a form, it's keys are empty and Request["txtTextField"] gives me nothing.

Any clue why?

回答1:

If you are using ASP.NET MVC, the input names need to be set with the "name" attribute rather than "id".

回答2:

You probably reset the form value in event handlers (such as page_load).

回答3:

If you are using ASP.NET 4.5 like me, use below hints

Disable auto Friendly URLs in a Web Form project
- settings.AutoRedirectMode = RedirectMode.Off; // in RouteConfig.cs
if you can:
- remove action="CILandingPage.aspx" from form element
- put a asp:button instead of normal button
- set PostBackUrl="~/CILandingPage.aspx" on your asp:button

more resources with more detail that was useful to me

Disable auto Friendly URLs in a Web Form project
http://www.mikesdotnetting.com request-form-is-empty-when-posting-to-aspx-page

回答4:

Another option is to capture your Request.Form[] data in Application_BeginRequest on the Global.asax.cs:

protected void Application_BeginRequest(object sender, EventArgs e)
{
    //capture form data and preserve in query string
    if (Request.Form["txtTextField"]!= null)
    {
        Response.Redirect(Request.RawUrl + "?txtTextField=" 
          + Request.Form["txtTextField"]);
    }
    //or preserve in Session variable
    if(Request.Form["txtTextField"]!=null)
    {
        Session["txtTextField"]=Request.Form["txtTextField"];
    }
}

The problem is that the form data is lost on the automatic redirect which is applied by friendlyUrls - if you store that data as something other than form data, it is unnecessary to turn off friendlyUrls or set AutoRedirectMode to RedirectMode.Off.

来源：https://stackoverflow.com/questions/2433624/why-is-my-asp-net-form-arriving-empty-when-i-post-from-page-to-page

标签

form-post

forms

http-post