只能從SQL數據庫

Question

我從通過此方法發送日期 WPF到ModelClass顯示日期.......

private void buttonNTSave_Click(object sender, RoutedEventArgs e) 
{ 
    ModelClass model = new ModelClass(); 
    model.TaskInsertion(textBoxNTSubject.Text, textBoxNTType.Text, Convert.ToDateTime(datePickerNT.SelectedDate), textBoxNTTitle.Text, textBoxNTDetail.Text); 
} 

的日期正在插入數據庫這種方法...

public void TaskInsertion(string subject, string type, DateTime dueDate, string title, string detail) 
{ 
    SqlConnection conn = new SqlConnection(connectionString); 
    try 
    { 
     string query = "INSERT INTO Tbl_Task (Email, Subject, Type, DueDate, Title, Detail) VALUES ('" + userEmail + "', '" + subject + "' , '" + type + "', '" + dueDate.Date + "', '" + title + "', '" + detail + "')"; 

     SqlCommand cmd = new SqlCommand(query, conn); 
     conn.Open(); 
     cmd.ExecuteNonQuery(); 
    } 

    catch (Exception e) 
    { 
     conn.Close(); 
    } 
} 

但每當我試着只檢索日期從數據庫到DataGrid中，仍然是時間與日期正顯示出..

public DataTable OverDueCurrentTask() 
{ 

    SqlConnection conn = new SqlConnection(connectionString); 
    try 
    { 

     DateTime DateToday = DateTime.UtcNow.Date; 
     string query = "DECLARE @sDate Date SET @sDate = '" + DateToday.Date + "' SELECT Title, Subject, Type, DueDate FROM Tbl_Task WHERE DueDate >= @sDate"; 

     SqlCommand cmd = new SqlCommand(query, conn); 
     conn.Open(); 
     cmd.ExecuteNonQuery(); 

     SqlDataAdapter dataAdp = new SqlDataAdapter(cmd); 
     DataTable dataTbl = new DataTable("Tbl_Task"); 
     dataAdp.Fill(dataTbl); 
     dataAdp.Update(dataTbl); 
     return dataTbl; 

    } 

    catch (Exception e) 
    { 

     conn.Close(); 
     return null; 

    } 
} 

如何顯示日期而不顯示時間？ N.B.在數據庫中，DueDate是日期類型列。

Answer 1

你需要投DueDate列cast([DueDate] as date) > = @sDate。而sDate已被宣佈爲date。

string query = @"DECLARE @sDate Date SET @sDate = '" + DateToday.Date + "' 
       SELECT Title, Subject, Type, cast([DueDate] as date) as DueDate FROM Tbl_Task 
       WHERE cast([DueDate] as date) >= @sDate"; 

儘管它完成了答案，但您需要對代碼進行微妙的更改，以避免SQL注入攻擊。使用SqlCommand Parameters。在代碼中添加using塊。

Answer 2

我相信你也可以在C＃中做到這一點。在SQL查詢中，你可以使用：

select cast([date] as date) as dateonly 

要將datetime轉換爲date。

下面編輯由丹·古斯曼提供：

的C＃代碼來構建應用程序所需的查詢字符串：

string query = "DECLARE @sDate Date SET @sDate = '" + DateToday.Date + "' SELECT Title, Subject, Type, CAST(DueDate AS date) AS DueDate FROM Tbl_Task WHERE DueDate >= @sDate;";