When accessing C # wi...">
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Change HtmlForm action in C # ASP.NET 3.5

I have a form like

<form id="form" action="" method="post" runat="server">

When accessing C # with code

HtmlForm form = (HtmlForm)this.FindControl("form");

and trying to change the action with

form.Attributes.Add("action","./newpage.aspx?data=data");

or

form.Attributes["action"] = "./newpage.aspx?data=data");

no changes are made. The form is still routed to one page. How can I dynamically change the action of a form in codebehind?

ADDITIONAL DETAILS: I have a page with the get variable. This variable must be sent in the action part of the form. So the response of page1 has getvar1. The form on page 1 should submit its data and getvar1. I was about to set this up with code in the action of the form, but would like to avoid using InnerHtml to write the entire form. Holly offered javascript, but I did not find a good way to get GET vars with javascript ...... just more information for the masses.

ANSWER: , @HollyStyles. javascript ajax-. - .

+5
6

Control Adapters asp.net.

:

public class RewriteFormHtmlTextWriter : HtmlTextWriter
{
    public RewriteFormHtmlTextWriter(HtmlTextWriter writer)
        : base(writer)
    {
        this.InnerWriter = writer.InnerWriter;
    }
    public RewriteFormHtmlTextWriter(System.IO.TextWriter writer)
        : base(writer)
    {
        base.InnerWriter = writer;
    }

    public override void WriteAttribute(string name, string value, bool fEncode)
    {
        if (name == "action")
        {
            value = "Change here your value"            
        }

        base.WriteAttribute(name, value, fEncode);
    }
}

App_Browsers Form.browser

<browsers>
  <browser refID="Default">
    <controlAdapters>
      <adapter controlType="System.Web.UI.HtmlControls.HtmlForm" adapterType="FormRewriterControlAdapter" />
    </controlAdapters>
  </browser>
</browsers>

. , .

: http://weblogs.asp.net/scottgu/archive/2007/02/26/tip-trick-url-rewriting-with-asp-net.aspx

+5

:

protected void Page_Init(object sender, EventArgs e)
{
    Form.Attributes.Add("action", "/Registration/Signup.aspx");
}
+1

, KB, , , ( : http://www.codeproject.com/Articles/23033/Change-your-ASP-NET-Form-s-Action-attribute-with-R).

, . , SetFormAction(string url) , <form action="url" />.

using System.IO;
using System.Text.RegularExpressions;
using System.Web;

/// 
/// The purpose of this class is to easily modify the form "action" of a given asp.net page.
/// To modify the action, call the following code in the code-behind of your page (or, better, your MasterPage):
/// Copied (and modified) from http://www.codeproject.com/KB/aspnet/ASP_Net_Form_Action_Attr.aspx
/// 
public class FormActionModifier : Stream
{
  private const string FORM_REGEX = "(]*>)";
  private Stream _sink;
  private long _position;
  string _url;
  public FormActionModifier(Stream sink, string url)
  {
    _sink = sink;
    _url = string.Format("$1{0}$3", url);
  }

  public override bool CanRead
  {
    get { return true; }
  }

  public override bool CanSeek
  {
    get { return true; }
  }

  public override bool CanWrite
  {
    get { return true; }
  }

  public override long Length
  {
    get { return 0; }
  }

  public override long Position
  {
    get { return _position; }
    set { _position = value; }
  }

  public override long Seek(long offset, System.IO.SeekOrigin direction)
  {
    return _sink.Seek(offset, direction);
  }

  public override void SetLength(long length)
  {
    _sink.SetLength(length);
  }

  public override void Close()
  {
    _sink.Close();
  }

  public override void Flush()
  {
    _sink.Flush();
  }

  public override int Read(byte[] buffer, int offset, int count)
  {
    return _sink.Read(buffer, offset, count);
  }

  public override void Write(byte[] buffer, int offset, int count)
  {
    string s = System.Text.UTF8Encoding.UTF8.GetString(buffer, offset, count);
    Regex reg = new Regex(FORM_REGEX, RegexOptions.IgnoreCase);
    Match m = reg.Match(s);
    if (m.Success)
    {
      string form = reg.Replace(m.Value, _url);
      int iform = m.Index;
      int lform = m.Length;
      s = string.Concat(s.Substring(0, iform), form, s.Substring(iform + lform));
    }
    byte[] yaz = System.Text.UTF8Encoding.UTF8.GetBytes(s);
    _sink.Write(yaz, 0, yaz.Length);
  }

  /// 
  /// Sets the Form Action to the url specified
  /// 
  public static void SetFormAction(string url)
  {
    if (HttpContext.Current != null)
      HttpContext.Current.Response.Filter = new FormActionModifier(HttpContext.Current.Response.Filter, url);
  } // SetFormAction()
} // class
0

, redirecttoaction

Here is an example

public ActionResult LogOff() {
FormsAuth.SignOut();
return RedirectToAction("Index", "Home");
}

Hope this helps.

0
source

I also had the same issue recently when posting the action attribute of a form would use a rewritten path, but I wanted to show the source url. I don't have url rewrite libraries.

I found that this page is very useful for the operation of my email programs: http://www.codeproject.com/Articles/94335/TIP-How-to-Handle-Form-Postbacks-when-Url-Rewritin

0
source

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