asp.netの更新クエリ

Question

私のプロジェクトでプロファイルの更新ページをプリフォームしようとすると、クエリがうまく機能しません。 以下のコード： が保護されたサブbtnSubmimt_Click（オブジェクトとして送信者、EventArgsのようe）はbtnSubmimt.Click 点心は、ハンドルのDataTable =新しいDataTableを（） DT =セッション（ "情報"）として

Dim connStr As String = ConfigurationManager.ConnectionStrings("ConnectionString").ConnectionString 

    Dim conn As SqlConnection = New SqlConnection(connStr) 
    conn.Open() 
    Dim cmd As SqlCommand = New SqlCommand() 
    Dim da As SqlDataAdapter = New SqlDataAdapter() 

    cmd.CommandType = CommandType.Text 
    cmd = New SqlCommand("Update [users] Set Email = @Email , Role = @Role , Country= @Country where UserName = @UserName") 

    cmd.Parameters.Add(New SqlParameter("@Email", txtEmail.Text.ToString)) 
    cmd.Parameters.Add(New SqlParameter("@Role", txtRole.Text.ToString)) 
    cmd.Parameters.Add(New SqlParameter("@Country", DDLCountry.SelectedValue.ToString)) 
    cmd.Parameters.Add(New SqlParameter("@UserName", Session("UserName"))) 
    cmd.Connection = conn 


    cmd.ExecuteNonQuery() 

    conn.Close() 



    ModalPopupExtender1.Show() 

End Sub 
Protected Sub Page_Load(sender As Object, e As EventArgs) Handles Me.Load 
    If Not IsPostBack Then 
     Dim dt As DataTable = New DataTable() 
     dt = Session("Info") 
     txtusername.Text = dt.Rows(0)("UserName").ToString 
     txtEmail.Text = dt.Rows(0)("Email").ToString 
     txtRole.Text = dt.Rows(0)("Role").ToString 
     DDLCountry.SelectedItem.Text = dt.Rows(0)("Country").ToString 
    End If 
End Sub 

Answer 1

DTますデータを取得していないので、DataTableおよびSqlDataAdapterは必要ありません。

Protected Sub btnSubmimt_Click(sender As Object, e As EventArgs) 
    Dim connStr As String = ConfigurationManager.ConnectionStrings("ConnectionString").ConnectionString 
    Dim cmdText As String = "Update [users] Set Email = @Email , Role = @Role, Country= @Country where UserName = @UserName" 
    Using conn = New SqlConnection(connStr) 
     Using cmd = New SqlCommand(cmdText, conn) 
      conn.Open() 
      cmd.Parameters.Add(New SqlParameter("@Email", txtEmail.Text)) 
      cmd.Parameters.Add(New SqlParameter("@Role", txtRole.Text)) 
      cmd.Parameters.Add(New SqlParameter("@Country", DDLCountry.SelectedValue)) 
      cmd.Parameters.Add(New SqlParameter("@UserName", Session("UserName"))) 
      cmd.ExecuteNonQuery() 
     End Using 
    End Using 
    ModalPopupExtender1.Show() 
End Sub