27 Comments

• Hmmm. This all makes sense, but I get an:
  
  Error: 'null' is null or not an object
  
  when I try to submit with an invalid entry in the reCaptcha...
  

• hi Aron, unfortunately that didn't make any sense. I'm including the full source i used throughout this post above, in the hopes that it may help you further.
  Good luck :-)
  

• Thank you, very useful.
  

• alessandro, thank you so much for sharing your solution. It wasn't working at first, but after adding ChildrenAsTriggers="false" it worked perfectly!
  

• Alessandro, what can I do if my Recaptcha is inside a MultiView which is encapsulated by a UpdatePanel? I applied your solution with no results. Thanks.
  

• hi Javier, it would be faster to test your issue at hand if you can post some pseudocode, that way i know exactly under what condition it's failing.
  

• Hi,
  
  Example works ok however it never returns a valid response. if the update panels are removed it works. any ideas?
  
  regards
  
  toby.
  

• Calling the Validate method fixes the failure ti validate:
  public void btnSubmit_Click(object sender, EventArgs args)
  {
  recaptcha1.Validate();
  if (!recaptcha1.IsValid)
  {
  labelError.Text = "Incorrect, try again!";
  labelError.ForeColor = System.Drawing.Color.Red;
  //Reload recaptcha
  ScriptManager.RegisterClientScriptBlock(
  this.Page,
  this.Page.GetType(),
  "whatever1",
  "Recaptcha.reload();",
  true);
  UpdatePanel2.Update();
  }
  }
  

• Hello ,
  I read above comments. Also I m getting same problem .
  do need to add
  " ScriptManager.RegisterClientScriptBlock(
  
  this.Page,
  
  this.Page.GetType(),
  
  "whatever1",
  
  "Recaptcha.reload();",
  
  true);"
  
  
  only you can update your update your update panel.
  problem will solved.
  Thanks
  

• I have copied this, however it always returns false, even if i type in the words correctly.?!
  
  any help?
  
  thanks
  

• I second Henrys problem. IT always returns false. Any solutions?
  

• Actually, I take it back. It doesn't return false, rather, nothing at all happens. I added the following to the code-behind:
  
  if (recaptcha1.IsValid)
  {
  labelError.Text = "Great!";
  labelError.ForeColor = System.Drawing.Color.Green;
  }
  
  but as mentioned, the code doesn't execute??
  

• I download your .dll file but its refference is not added into asp page . please tell me how we can add refference in asp.net.
  
  thanks for helf
  

• Great code dude its really working
  

• Amazing job!!thanks for the article....
  

• Encountering the same problem as Henry and Phil.
  Page.IsValid is always false.
  What is the solution?
  

• do recaptcha works on localhost?
  if yes, please tell me what is the process???
  
  I tried all above said, but I am getting always false in recaptcha.validate() method.
  
  please help me...
  

• What happens if the public and private keys are invalid?
  

• Thanks pal, the code worked and I have got the desired output with the code.
  
  Best Regards,
  Sougandh Pavithran
  INDIA
  

• Hi Sougandh,
  
  Still Page.IsValid/recaptcha1.Isvalid always returns false.
  How did you get a desired output? Please let me know.
  
  Thanks,
  Kameswari.
  

• wa
  

• Thanks for your help! I needed to solve it!
  

• I'm having a problem with this, it works for me but only on the first time I land on the page (like by typing the url in the browser). The reCaptcha is in my Master Page hidden in a JQueryUI dialog (modal). When I first land on the page everything works great, I can show the modal, use the form, and everything works. If i navigate to any other page using that master page, the page finishes loading, then automatically gets redirected to the reCaptcha on a blank white page...
  
  Any thoughts?
  

• I tried this, however i keep getting a error still in recaptcha.js at e("recaptcha_challenge_field_holder") is null.Can u pls help...
  

• Solution: ScriptManager.RegisterStartupScript(this.Page, this.Page.GetType(), "whatever1", "Recaptcha.reload();", true);
  

• Thank you very much! Your solution worked nice!
  

• Hi all,
  
  Recaptcha disappears after postback while using updatepanel. Doing the Recaptcha.Reload() does not solve the issue?
  
  Any help will be very appreciated.
  
  Thanks