In my ASP.NET Web forms application, I am adding a feature to upload files but I don't want to do a full postback. So to make it asynchronous I thought of using UpdatePanel.
This UpdatePanel contains a FileUpload control and a button to upload the selected photo. When I was debuggin my code to detect if file is actually selected or not, I found FileUpload's HasFile property to be false.
It works when I remove UpdatePanel but I don't understand why.
To help you understand, here is the code:
ASPX markups:
<asp:UpdatePanel ID="UPProf" runat="server">
<ContentTemplate>
<asp:FileUpload ID="FUDP" runat="server" />
<asp:Button ID="BUDP" runat="server" OnClick="BUDP_Click" Text="Upload your photo" />
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="BUDP" EventName="Click" />
</Triggers>
</asp:UpdatePanel>
Here's its CS code:
protected void BUDP_Click(object sender, EventArgs e)
{
try
{
if (FUDP.HasFile) // code doesn't pass this if condition
{
FUDP.SaveAs("D:/Pictures/" + count + ".jpeg"); //it doesn't work since there is no file here
}
else
{
//Set some message for user
}
}
catch (Exception ex)
{
//log the error
}
}
Upload requires full page request. This is a limitation of the XmlHttpRequest component used in all AJAX frameworks for asynchronous calls to the application.
Remove the UpdatePanel or make BUDP button to perform postbacks.
<asp:UpdatePanel ID="UPProf" runat="server">
<ContentTemplate>
<asp:FileUpload ID="FUDP" runat="server" />
<asp:Button ID="BUDP" runat="server" OnClick="BUDP_Click"
Text="Upload your photo" />
</ContentTemplate>
<Triggers>
<asp:PostBackTrigger ControlID="BUDP" />
</Triggers>
</asp:UpdatePanel>
Related
I have an update panel, in that update panel I have a repeater control and in that repeater control I have file upload control where I am attaching file on each row.
I have another update panel, in this I have a save button, whenever I am trying to click this save button and looping through the above mentioned repeater to check file exists in file upload control it always give me false i.e the file upload control is cleared.
I want to know how can I preserve the file in fileupload control with the existing scenario.
Thank you
You need to register the Button for an PostBack. So add a Trigger to the UpdatePanel containing that Button.
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<ContentTemplate>
<asp:Repeater ID="Repeater1" runat="server">
<ItemTemplate>
<asp:FileUpload ID="FileUpload1" runat="server" />
</ItemTemplate>
</asp:Repeater>
</ContentTemplate>
</asp:UpdatePanel>
<asp:UpdatePanel ID="UpdatePanel2" runat="server">
<ContentTemplate>
<asp:Button ID="Button1" runat="server" Text="Button" OnClick="Button1_Click" />
</ContentTemplate>
<Triggers>
<asp:PostBackTrigger ControlID="Button1" />
</Triggers>
</asp:UpdatePanel>
Now you can process the files on the Button click.
protected void Button1_Click(object sender, EventArgs e)
{
foreach (RepeaterItem item in Repeater1.Items)
{
FileUpload fu = item.FindControl("FileUpload1") as FileUpload;
if (fu.HasFile)
{
//process file here
}
}
}
If i am using update panel then PostedFile not giving file path some error are coming and if update panel are removed the page then excel file successfully upload how to solve
your code should be as shown below
<asp:UpdatePanel runat="server" ID="UpdatePanel1" UpdateMode="Conditional">
<ContentTemplate>
<asp:FileUpload runat="server" ID="flFile" />
<asp:Button runat="server" ID="btnSubmit" Text="Upload" OnClick="btnSubmit_Click" />
</ContentTemplate>
<Triggers>
<asp:PostBackTrigger ControlID="btnSubmit" />
</Triggers>
</asp:UpdatePanel>
You need to put postback trigger if you are uploading any files.
A FileUpload inside UpdatePanel won't work. You have to post the whole page. You do this by adding a PostBackTrigger to the button you use for uploading files.
Something like this (see Triggers):
<asp:UpdatePanel ID="upnlMain" runat="server" UpdateMode="Conditional">
<ContentTemplate>
<asp:FileUpload ID="fileUpload" runat="server" Width="400px" />
<asp:Button ID="btnUploadFiles" runat="server" Text="Upload files" />
</ContentTemplate>
<Triggers>
<asp:PostBackTrigger ControlID="btnUploadFiles" />
</Triggers>
</asp:UpdatePanel>
If you have problems with not posting the first time a button is clicked then add this to Page Load event:
Page.Form.Attributes.Add("enctype", "multipart/form-data");
I have put asp button in update panel and asp file uploader in outside of update panel in server side button click function i am geting file uploader empty.give me any idea..my code is below
<asp:FileUpload runat="server" ID="DecFormUpload"/>
<asp:UpdatePanel runat="server" ID="UpdateDecForm" UpdateMode="Conditional">
<ContentTemplate>
<asp:Button ID="DecFormUploadClick" OnClick="DecFormUploadClick_Click" OnClientClick="return DecFormUploadClick_Save();" runat="server" Text="Upload" />
</ContentTemplate>
</asp:UpdatePanel>
c# code
protected void DecFormUploadClick_Click(object sender, EventArgs e)
{
if(DecFormUpload.HasFile)//my problem is getting false here
{
}
}
This issue is due to that FileUpload needs a full postback, add the following just after your :
<Triggers>
<asp:PostBackTrigger ControlID="DecFormUploadClick" />
</Triggers>
Hope it helps
I have an AJAX UpdatePanel and a GridView inside it. A FileUpload component outside the updatepanel.
<asp:FileUpload ID="documentUpload" runat="server" />
<asp:Button ID="btnUploadDocumentDetails" runat="server" OnClick="btnUploadDocumentDetails_Click" />
<asp:UpdatePanel ID="UpdatePanel_DocumentDetails" runat="server">
<Triggers>
<asp:AsyncPostBackTrigger ControlID="btnuploaddocumentdetails" EventName="Click" />
</Triggers>
<ContentTemplate>
<asp:GridView ID="gvDocuments" runat="server"></asp:GridView>
</ContentTemplate>
</asp:UpdatePanel>
On button click I have to upload the file on the server and update the GridView (gridview contains the list of all files).
Problem:
When I click on the button to upload the file, the FileUpload component gets empty (HasFile attribute returns false).
How can I resolve this issue to asynchronously update the GridView?
I am uploading file using ASP.net File upload control.
My FileUpload1.HasFile is always returning false.
if (FileUpload1.HasFile)
{
DBOperations db = new DBOperations();
try
{
FileUpload1.SaveAs(Server.MapPath("~/uploadedImages/" + db.uploadImage(System.IO.Path.GetExtension(FileUpload1.FileName)) + System.IO.Path.GetExtension(FileUpload1.FileName)));
}
catch (Exception Ex)
{
String he = Ex.Message;
}
}
I am using following ASP.net Code
<asp:UpdatePanel ID="fileUpload" runat="server">
<ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="btnUploadFile" EventName="Click" />
</Triggers>
<asp:FileUpload ID="FileUpload1" runat="server" />
<asp:Button ID="btnUploadFile" Text="Upload File" runat="server"
onclick="btnUploadFile_Click" />
<br />
<asp:RegularExpressionValidator ID="revImage" ControlToValidate="FileUpload1" ValidationExpression="^.*\.((j|J)(p|P)(e|E)?(g|G)|(g|G)(i|I)(f|F)|(p|P)(n|N)(g|G))$" Text="Invalid image type" runat="server" />
</ContentTemplate>
</asp:UpdatePanel>
I have tried even by removing AsyncPostBackTrigger and even by removing Whole asp:updatePanel then also my FileUpload1.HasFile always returns false.
ASP.NET's "AJAX" thing doesn't support file uploads in UpdatePanels out of the box. Change that trigger into a PostBackTrigger (which causes a full page load) or use something else to upload the file.
Add a trigger for your UpdatePanel
<Triggers>
<asp:PostBackTrigger ControlID="btnUploadFile" />
</Triggers>
This will force a postback when the upload button is clicked.
Also add the line below to the Page_Load
Page.Form.Attributes.Add("enctype", "multipart/form-data");
I know this post if old, but I found that if the file is empty [ 0 KB ] then it will return false as well. There has to be something in the file in order for .HasFile to acknowledge it.