ASP.NET - File Uploading
ASP.NET has two controls that allow users to upload files to the web server. Once the
server receives the posted file data, the application can save it, check it, or ignore it.
The following controls allow the file uploading:
HtmlInputFile - an HTML server control
FileUpload - and ASP.NET web control
Both controls allow file uploading, but the FileUpload control automatically sets the
encoding of the form, whereas the HtmlInputFile does not do so.
In this tutorial, we use the FileUpload control. The FileUpload control allows the user to
browse for and select the file to be uploaded, providing a browse button and a text box
for entering the filename.
Once, the user has entered the filename in the text box by typing the name or
browsing, the SaveAs method of the FileUpload control can be called to save the file to
the disk.
The basic syntax of FileUpload is:
<asp:FileUpload ID= "Uploader" runat = "server" />
The FileUpload class is derived from the WebControl class, and inherits all its
members. Apart from those, the FileUpload class has the following read-only
properties:
Properties Description
FileBytes Returns an array of the bytes in a file to be uploaded.
FileContent Returns the stream object pointing to the file to be uploaded.
FileName Returns the name of the file to be uploaded.
HasFile Specifies whether the control has a file to upload.
PostedFile Returns a reference to the uploaded file.
