Step 1: Add html input type as file
<input id ="uploadFile" type="file" runat="server" />
Step 2: Create a button to upload file in the server
<asp:Button ID="Button1" runat="server" OnClick="Button1_Click" />
Step 3: Create a folder in the web project like “TempFiles”
Step 4: Upload file in the server.
protected void Button1_Click(object sender, EventArgs e) { if (this.uploadFile.PostedFile != null) { // Get a reference to PostedFile object HttpPostedFile huploadFile = uploadFile.PostedFile; // Get size of uploaded file int nFileLen = huploadFile.ContentLength; decimal fileSize = uploadFile.PostedFile.ContentLength / 1024; if (fileSize > 100) //If file size is no more than 100 KB { this.lblMsg.Text = "Size of this image is greater than 100KB"; return; } byte[] scriptData = new byte[nFileLen]; // Read uploaded file from the Stream huploadFile.InputStream.Read(scriptData, 0, nFileLen); string filePath = Server.MapPath("TempFiles"); filePath = filePath + "\\" + Path.GetFileName(uploadFile.PostedFile.FileName); //concate filename with file path FileStream newFile = new FileStream(filePath, FileMode.Create); // Write data to the file newFile.Write(scriptData, 0, scriptData.Length); // Close file newFile.Close(); } else { lblMsg.Text = "This is an empty file"; } }