对SqlHelper的理解(二)
As DataTable
Dim strConnStr As String = System.Configuration.ConfigurationManager.AppSettings("ConnStr")
Dim conn As SqlConnection = New SqlConnection(strConnStr)
Dim cmd As New SqlCommand
Dim adataset As DataSet
Dim adaptor As SqlDataAdapter
cmd = New SqlCommand(cmdTxt, conn)
cmd.CommandType = cmdType
adaptor = New SqlDataAdapter(cmd)
adataset = New DataSet
Try
If conn.State = ConnectionState.Closed Then
conn.Open()
End If
adaptor.Fill(adataset)
Catch ex As Exception
MsgBox(ex.Message, , "数据库打开")
Finally
If conn.State = ConnectionState.Open Then
conn.Close()
End If
End Try
Return adataset.Tables(0)
End Function
End Class
总结
在面向对象的学习中，我们知道当遇到两个以上的需求或用到两次以上的方法时我们就要考虑把它封装起来。SqlHelper类就是体现了封装的思想，它的提出是给了我们一个思路，其代码是根据具体情况具体分析的，切莫教条主义。