为特定用户添加图像和路径到数据库

Question

protected void Upload(object sender, EventArgs e)
    {
        //Extract Image File Name.
        string fileName = Path.GetFileName(FileUpload1.PostedFile.FileName);

        //Set the Image File Path.
        string filePath = "~/Uploads/" + fileName;

        //Save the Image File in Folder.
        FileUpload1.PostedFile.SaveAs(Server.MapPath(filePath));
        string mycon = "server =localhost; Uid=root; password = ; persistsecurityinfo = True; database =ovs; SslMode = none";

        MySqlConnection con1 = new MySqlConnection(mycon);
      //  string sql = "INSERT INTO candidate VALUES(@Name, @Path)";
        MySqlCommand cmd = null;
        cmd = new MySqlCommand("INSERT INTO candidate(candidateImage,path where studentID ='" + Session["UserName"] + "') VALUES (@Name,@Path)", con1);

                cmd.Parameters.AddWithValue("@Name", fileName);
                cmd.Parameters.AddWithValue("@Path", filePath);
        con1.Open();
        cmd.ExecuteNonQuery();
        con1.Close();
    }

当用户点击上传按钮时，图片和路径将被保存到属于特定用户的数据库中。比如ID为R1001的用户登录自己的账号，点击上传按钮，图片和路径就会保存在数据库中的R1001下。我显示错误消息，提示存在语法错误，但我无法找到它

database

Answer 1

当您想向表中插入数据时，您不需要Where。 我在您的command 中删除了where，并为sessionId 使用了一个参数。

     protected void Upload(object sender, EventArgs e)
    {
        //Extract Image File Name.
        string fileName = Path.GetFileName(FileUpload1.PostedFile.FileName);

        //Set the Image File Path.
        string filePath = "~/Uploads/" + fileName;

        //Save the Image File in Folder.
        FileUpload1.PostedFile.SaveAs(Server.MapPath(filePath));
        string mycon = "server =localhost; Uid=root; password = ; persistsecurityinfo = True; database =ovs; SslMode = none";

        MySqlConnection con1 = new MySqlConnection(mycon);
        //  string sql = "INSERT INTO candidate VALUES(@Name, @Path)";
        SqlCommand cmd = null;
        string command = "update candidate set candidateImage=@Name ,path = @Path where StudentID=@studnetId";
        cmd = new MySqlCommand(command, con1);
        
        cmd.Parameters.AddWithValue("@Name", fileName);
        cmd.Parameters.AddWithValue("@Path", filePath);
        cmd.Parameters.AddWithValue("@studnetId", Session["UserName"]??""); // if student id is accept number in database, you must convert it to int
        con1.Open();
        cmd.ExecuteNonQuery();
        con1.Close();
    }