Solved

Using AJAX.NET how do you clear an uploadfile control?

Posted on 2011-02-15
9
1,315 Views
Last Modified: 2012-06-27
I have a regular upload file control inside an AJAX.NET updatepanel.  If I use it to upload a file once, its no problem; however, if i hit the submit button again, even though the text box is clear, it is still attached to the previous file uploaded.

How do I clear that so that I may use the uploadfile control freshly?
0
Comment
Question by:RichardRiga
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 5
  • 2
  • 2
9 Comments
 
LVL 16

Accepted Solution

by:
Kamal Khaleefa earned 250 total points
ID: 34904109
0
 
LVL 1

Author Comment

by:RichardRiga
ID: 34910571
That's a neat article but how do I call a javascript function after the .NET webservice code has completed its work?
0
 
LVL 16

Expert Comment

by:Kamal Khaleefa
ID: 34914764
regarding to Ur  question
but a JavaScript function to see if the file upload is empty

 var FileUpload1="<%=FileUpload1.ClientID %>"
function CheckForTestFile()
   {
        var file = document.getElementById(FileUpload1);
        var fileName=file.value;        
        //Checking for file browsed or not
        if (Trim(fileName) =='' )
        {
            alert("Please select a file to upload!!!");
            file.focus();
            return false;
        }
 }
and on ur button
add this

 <asp:Button ID="btnUpload" runat="server"  OnClientClick="if(CheckForTestFile()){return true}else{return false}"
                                                  text="Upload File" TabIndex="50" EnableViewState="False" />
                                           
0
MS Dynamics Made Instantly Simpler

Make Your Microsoft Dynamics Investment Count  & Drastically Decrease Training Time by Providing Intuitive Step-By-Step WalkThru Tutorials.

 
LVL 1

Author Comment

by:RichardRiga
ID: 34916726
These methods don't seem to work still.  I have inserted them into the proper places and they are being executed; however, the fileupload control still reports that it has contents when trying to upload a blank file'
0
 
LVL 1

Author Comment

by:RichardRiga
ID: 34917036
My apologies!!  I completely forgot to mention that I wasn't using an ASP:FileUpload control.  I'm using the AsyncFileUpload control from the AjaxToolkit.  I'm not sure it makes a difference in your answers;however, I should have added that.
0
 
LVL 83

Assisted Solution

by:CodeCruiser
CodeCruiser earned 250 total points
ID: 34917067
>however, the fileupload control still reports that it has contents when trying to upload a blank file'
Do you mean you are uploading a 0 byte file?
0
 
LVL 1

Author Comment

by:RichardRiga
ID: 34918554
Here is what happens:

1.  I use the control to upload a file.  That works, no problem.  
     At this point the control's field resets itself to appear empty.
     Since the field is empty, at this point, if I hit the submit button again, the property fuFileUpload.HasFile should be False.  But its not.  It returns true.

2.  So i use a script:
            function clearContents() {
                 var AsyncFileUpload = $get("<%=fuFileUpload.ClientID%>");
                 var txts = AsyncFileUpload.getElementsByTagName("input");
                 for (var i = 0; i < txts.length; i++) {
                     if (txts[i].type == "text") {
                         txts[i].value = "";
                         txts[i].style.backgroundColor = "white";
                     }
                 }
             }

and call on that script when the file is uploaded with:
<cc1:AsyncFileUpload ID="fuFileUpload" runat="server" OnClientUploadComplete="<%UploadComplete() %>" />

Codebehind has:
    Public Sub CallUploadComplete()
        ClientScript.RegisterStartupScript(Me.GetType(), "removeDoc", "ClearContents()", True)
    End Sub

Something isn't right.  Can anyone fix those three snippets of code to make it work?  I beg!  
And thanks.

Open in new window

0
 
LVL 83

Expert Comment

by:CodeCruiser
ID: 34924555
What does the

IsNothing(fuFileUpload.PostedFile)

return?
0
 
LVL 1

Author Closing Comment

by:RichardRiga
ID: 35028696
Project was scrapped.  Apologies for the waste of time, but thank you for being respondent
0

Featured Post

Enroll in June's Course of the Month

June's Course of the Month is now available! Every 10 seconds, a consumer gets hit with ransomware. Refresh your knowledge of ransomware best practices by enrolling in this month's complimentary course for Premium Members, Team Accounts, and Qualified Experts.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

The ECB site provides FX rates for major currencies since its inception in 1999 in the form of an XML feed. The files have the following format (reducted for brevity) (CODE) There are three files available HERE (http://www.ecb.europa.eu/stats/exch…
International Data Corporation (IDC) prognosticates that before the current the year gets over disbursing on IT framework products to be sent in cloud environs will be $37.1B.
Come and listen to Percona CEO Peter Zaitsev discuss what’s new in Percona open source software, including Percona Server for MySQL (https://www.percona.com/software/mysql-database/percona-server) and MongoDB (https://www.percona.com/software/mongo-…
Add bar graphs to Access queries using Unicode block characters. Graphs appear on every record in the color you want. Give life to numbers. Hopes this gives you ideas on visualizing your data in new ways ~ Create a calculated field in a query: …

717 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question