I am using a file-upload object on my webpage with an "upload" button and a "Status" label. When a file is successfully upload the label's text changes to "File uploaded". If a user would like to upload another file, I want to clear the label text because as it still says "File Uploaded". Not sure how to do this. Please help.
It appears the instantiating a new FileUpload object or clearing the FileUpload attributes are the best leads, as mentioned in this existing SO question:
Here is a similar SO question How to clear file upload text in server side (c#)
You have two way to do this:
client side
Page will be reloaded if file uploaded, you just need to clear the label when page is loaded.
Server side
You can clear it with setting the text of "Status" label to blank after your codes handling uploaded file.
Related
I am using an AjaxFileUpload for multiple file upload. It is working, but I want to change the destination with the value in a textbox. The code is below which is in the AjaxFileUpload1_onUploadComplete method:
string myDir= myDirTextBox.Text.Trim();
AjaxFileUpload1.SaveAs(Server.MapPath("../allarticles/"+ myDir+"/"+e.FileName));
I debug the project and write a name in the myDirTextBox. Then when I click the Upload File button the value of this textbox is always null. That's why I can't change the destination dynamically.
I have read this article but it is not clear: upload multiple files with ajaxFileUpload with different file ids
What is the problem and how can I solve it?
When server event occurs the page goes through complete page lifecycle.
That means your code deals with new, uninitialized version of a page which is not related in any way with the page you see in a browser.
To save the value of a textbox and utilize it later you need to write some code to store this value between page requests. This can be simple JavaScript code attached to Upload button, that posts textbox value with AJAX to a server. Server, in turn, will store this value in session or another persistent storage.
How can I add a file browse functionality on my asp.net web form ?
I have a similar button in my winforms app and now I need it on asp.net my web page.
FileUpload control is used to select and post file to a web server, I just need to select file path/name without sending file.
Should I add some JS to delete FORM item before doing POST or any other simplier solution exists ?
Follow this.
You can use asp:FileUpload , when user selects a file, you need to get that path using this - document.getElementById("fileeupload_id").value. Save this value to hidden field , say with id hdn.
Reset file selection using this - document.getElementById("fileeupload_id").value = "".
So that, when page will be posted, you file will not be posted,rather filename will be posted as hdn.Use Request.Form["hdn"] to get selected file path.
In my website,I have a home page in which by clicking on an image button,I get redirected to a different .apsx page .This page consists of a FileUpload control and 2 buttons(ATTACH,CANCEL).When a user selects/browses a file from his local machine and click ATTACH button,I display that file in a GRIDVIEW and also push the details of that file like Filename into a DATATABLE.
The user in this way can browse multiple files and all of them are added to GridView and also pushed to DATATABLE.Now when the user clickes CANCEL button,I am sending the whole DATATABLE in a session object to the HOME page.Upon clicking SAVE button in the home page,the files in the DATATABLE must get stored in a physical location that I mention in the code.
The problem that I am facing is that when I write
FileUpload fl=new FileUpload;
fl.SaveAs(dt["fileName"]);
The files are not at all getting saved in the location.
However If I pass the FileUpload control using Session from the second page,
FileUpload fl=(FileUpload)Session["FileUpload"]
The files are getting saved with the correct filenames but the content of all the files consists of the content of the latest uploaded file.I know what the problem is but unable to get a solution.
My Requirement is to save the files in a physical path only after clicking the Save button in the home page.Kindly Suggest me..Thanks in advance!
I believe that the asp.net FileUpload control only supports uploading of one file at a time. that is why you only see the contents of the last file. You either need to create a separate control for each upload, roll your own, or use a 3rd-party vendor control.
I'm using an asp:FileUpload control to give the user the chance to look for an image on the hard drive, once the user has chosen the image, after a button is pressed, I want to display the image in an asp:Image control.
I've been trying to get the full path of the file but I can't get it, I'm using Path.GetFullPath(FileUpload.FileName) but I'm getting a totally different path, not the path to the image that the user selected.
I was reading that I need to set the src attribute of the asp:Image control to be an aspx page which is going to return the image, and then I have to write the bytes from the image to the response but I'm not sure how to do this (I'm a newbie in web development), I don't know what should I put in my event, in the code behind, or what code should I place on the aspx page that will return the image, neither how to call the aspx page with the image from the event handler.
Can anyone show me a good example on how to achieve this please?
The issue here is the file being uploaded resides on the client computer where the asp:image control is looking for an image on the server computer.
What you should be doing is on the form submit/button click save the file into the application folder then reference that file with your asp:image control.
You can use the project mentioned below to preview the image before uploading. Working sample is also attached.
http://www.dotnetspider.com/resources/40858-Preview-Image-before-uploading-using.aspx
This uses AjaxControlToolKit's AsyncFileUploadControl and HTTPHandler to upload the image.
I am creating FileUpload controls at run time. When I click a LinkButton a new FileUpload control is generated.
Now suppose I have selected a file from a FileUpload control and I click the LinkButton. The previous FileUpload control loses its path. However, I'm maintaining the ViewState of each control that I create at runtime by using this line:
f1.enableviewstate = true;
How do I maintain the selected file for a FileUpload control?
Steps
user selects a file
user click LinkButton (issues a postback that adds additional file uploading control)
server side should get the file on postback and store it somewhere (anywhere)
replace first <input type=file> with something like Label and check mark icon (to tell user the file has already been uploaded (or even a read-only text box with disabled browse button to fake file upload control - however you won't be able to display correct file path in it)
user is presented with a new form that has new empty file upload control in showing already uploaded files.
For security reasons you can't manipulate <input type=file> in any way shape or form.
Hack approach
If I understood you correctly your link button adds additional file upload controls to your page. Instead I'd create a sufficient number of upload controls the first time and display just one. Others would be hidden by CSS. After user clicks the LinkButton, it would however have only client-side Javascript functionality that would reveal additional control. And another... and another... and another... until maximum is reached.
Complex approach
You could however make it in a different way by using more Javascript and make it more Web 2.0-ish. You should however upload those files via <iframe>
as some of the others mentioned, you cannot preserve the viewstate of a FileUpload due to security issues.
What you could do is to simply add a Label just below the FileUpload. When the user clicks on the linkbutton in order to generate a new FileUpload, a postback will be fired where you could check whether the FileUpload controls present on the page have some value (i.e. the user already selected a file to upload), and if so, you could directly start to upload that file and show the result (the path or filename) on the label, just that the user knows he has added that file already. You could also hide the fileupload and additionally add a remove link to again remove the uploaded file (similar approach as Gmail does).
Hope this helped.
Juri
You can't pre-select a file path in the file upload input tag (security related - the user must select the file), so .Net is not able to populate the value from viewstate.
Consider if you really need to at it at runtime?
If you really need to at runtime; Don't forget to add it to the closest container's Controls property. Doing this makes sure it's state is serialized to the ViewState.
Hope this helps...
as per me there is no way to persist viewstate of fileupload in asps.net.
u can store it's value in hidden field,session etc file u can not be able to assign that value to again file upload because it is read only