Question

我试图将数据从数据库显示到文本框，这是我在文本框中写的内容。这是我的最后一个代码。这里的数据显示在datagrid中。而不是datagrid如何将数据获取到文本框。

Public Sub SelectItem(ByVal ItemCode As String)
    Try
        sql.OpenDbConnection()
        Dim strSQL As String = "SELECT ItemCode 'Item Code',ItemName 'Item Name' " & _
  " FROM tblItemMaster where ItemCode= @ItemCode"
        Dim cmd As New SqlCommand(strSQL, sql.SqlConn)
        Dim ds As New DataSet

        cmd.Parameters.AddWithValue("ItemCode", ItemCode)

        Dim da As New SqlDataAdapter(cmd)
        da.Fill(ds, "tblItemMaster")
        dgvPurchaseOrder.DataSource = ds.Tables("tblItemMaster")
        sql.SqlConn.Close()
    Catch ex As SqlException
        MsgBox(ex.Message, MsgBoxStyle.Critical, "SQL Error")
    Catch ex As Exception
        MsgBox(ex.Message, MsgBoxStyle.Critical, "General Error")
    End Try
End Sub

我不知道该怎么做。请帮帮我

Answer 1

如果你想填充文本框，请尝试类似......

Public Sub SelectItem(ByVal ItemCode As String)
Try
    sql.OpenDbConnection()
    Dim strSQL As String = "SELECT ItemCode [Item Code],ItemName [Item Name] FROM tblItemMaster where ItemCode= @ItemCode"
    Dim cmd As New SqlCommand(strSQL, sql.SqlConn)
    cmd.Parameters.AddWithValue("ItemCode", ItemCode)
    Dim myReader As sqlDataReader 

    myReader = cmd.ExecuteReader()
    If myReader.HasRows Then
        myReader.Read() 
        txtItemCode.Text = myReader.GetValue(0).ToString()
    txtItemName.Text = myReader.GetValue(1).ToString()

    Else
       MessageBox.Show("No data found", "No Data")
    End If
    myReader.Close()

    sql.SqlConn.Close()
    Catch ex As SqlException
        MsgBox(ex.Message, MsgBoxStyle.Critical, "SQL Error")
    Catch ex As Exception
        MsgBox(ex.Message, MsgBoxStyle.Critical, "General Error")
End Try
End Sub

Answer 2

以下代码应将ItenName，Qty和Price返回到名为TxtName，txtQty和txtPrice的文本框中。如果您想要检索单个值，则根本不需要DataSet。

Public Sub SelectItem(ByVal ItemCode As String)
        Try
            sql.OpenDbConnection()
            Dim strSQL As String = "SELECT ItemName, Qty, Price " & _
                                   "FROM tblItemMaster WHERE ItemCode = @ItemCode"
            Dim cmd As New SqlCommand(strSQL, sql.SqlConn)
            cmd.Parameters.AddWithValue("@ItemCode", ItemCode)
            Dim reader As SqlDataReader
            reader = cmd.ExecuteReader()
            If reader.HasRows Then
               reader.Read() 
               txtItemName.Text = reader.GetValue(0)
               txtQty.Text = reader.GetValue(1).ToString()
               txtPrice.Text = reader.GetValue(2).ToString()
               reader.Close()
            End If
    Catch ex As SqlException
        MsgBox(ex.Message)
    End Try
End Sub

显示从数据库到文本框的数据

2 个答案: