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Why FileUpload HasFile is always false?

Why FileUpload HasFile is always false?

HasFile is also false if you upload an empty file. In this case, adding some text to the file, you want to upload will make the Has file property return true.

Why FileUpload HasFile is always false with AJAX UpdatePanel?

Hence when you place FileUpload control in AJAX UpdatePanel and try to upload the file asynchronously using the PostedFile property is always NULL and the HasFile property is always false. This happens because FileUpload control does not work with partial PostBack which is done in UpdatePanel.

What is HasFile?

Remarks. The HasFile property gets a value indicating whether the FileUpload control contains a file to upload. For example, before calling the SaveAs method to save the file to disk, use the HasFile property to verify that the file exists. If HasFile returns true , call the SaveAs method.

What is FileUpload HasFile in c#?

FileUpload is an asp.net web server control. FileUpload control’s HasFile property allow us to determine whether user select a file to upload. if an user does not select a file to upload and press the upload button then we can verify it by using FileUpload control’s HasFile property.

When does fileupload.hasfile return false?

Turn out that FileUpload.HasFile is also false if you upload an empty file. In this case, adding some text to the file, you want to upload will make the Has file property return true.

When to use the hasfile property in Microsoft Office?

For example, before calling the SaveAs method to save the file to disk, use the HasFile property to verify that the file exists. If HasFile returns true, call the SaveAs method. If it returns false, display a message to the user indicating that the control does not contain a file.

When to use the hasfile and saveas methods?

Before saving the file, the HasFile method is called to verify that the control contains a file to upload. In addition, the File.Exists method is called to check whether a file with the same name already occurs in the path. If it does, the name of the file to upload is prefixed with an underscore character before the SaveAs method is called.

Is it possible to upload a file using Ajax?

You cannot upload files using AJAX => you should not be placing a FileUpload control inside an UpdatePanel because this UpdatePanel sends an AJAX request to the server. I also uploaded a file using the FileUpload control, but the HasFile property returned false.