Upload File without Submit Button click using FileUpload control in ASP.Net

This way

HTML

<asp:FileUpload ID="FileUpload1" runat="server" />
<br />
<asp:Label ID="lblMessage" runat="server" Text="File uploaded successfully." ForeColor="Green"
    Visible="false" />
<asp:Button ID="btnUpload" Text="Upload" runat="server" OnClick="Upload" Style="display: none" />
<script type="text/javascript">
    function UploadFile(fileUpload) {
        if (fileUpload.value != '') {
            document.getElementById("<%=btnUpload.ClientID %>").click();
        }
    }
</script>

Namespace

C#

using System.IO;

VB.Net

Imports System.IO

Code

C#

protected void Page_Load(object sender, EventArgs e)
{
    FileUpload1.Attributes["onchange"] = "UploadFile(this)";
}
protected void Upload(object sender, EventArgs e)
{
    FileUpload1.SaveAs(Server.MapPath("~/Uploads/" + Path.GetFileName(FileUpload1.FileName)));
    lblMessage.Visible = true;
}

VB.Net

Protected Sub Page_Load(sender As Object, e As EventArgs) Handles Me.Load
    FileUpload1.Attributes("onchange") = "UploadFile(this)"
End Sub
Protected Sub Upload(sender As Object, e As EventArgs)
    FileUpload1.SaveAs(Server.MapPath("~/Uploads/" + Path.GetFileName(FileUpload1.FileName)))
    lblMessage.Visible = True
End Sub

Screenshot