Question

我是新上课的，我想创建一个SqlCommandManager课程，但我无法弄清楚如何在课堂上传递SqlParameter。

例如，如果我想插入数据，我会像下面的客户端一样使用我的类。

'Client

Dim m_SqlComManager as new SQLCommandManager("MyConnectionString")
m_SqlCommandManager.Commandtext = "INSERT INTO [TableName]([Field1],[Field2])VALUES(@Field1,Field2);"
m_SqlCommandManager.Parameters.AddWithValue("@Field1","SomeValue1")
m_SqlCommandManager.Parameters.AddWithValue("@Field2","SomeValue2")
m_SqlCommandManager.ExecuteNonQuery()


'Here is my class

Imports System.Data.SqlClient
Public Class SQLCommandManager
Private m_SqlParameters As SqlParameter()
Private m_Commandtext As String
Private m_ConStr As String

Public WriteOnly Property SQlParameter() As SqlParameter()
    Set(ByVal value As SqlParameter())
        value = m_SqlParameters
    End Set
End Property

Public Property CommandText() As String
    Get
        Return m_Commandtext
    End Get
    Set(ByVal value As String)
        value = m_Commandtext
    End Set
End Property

Public Sub New(ByVal con As String)
    m_ConStr = con
End Sub

Public Sub ExecuteNonQuery()
    Using con As New SqlConnection(m_ConStr)
        Using com As New SqlCommand
            com.Connection = con
            com.CommandText = m_Commandtext
            'Please help
            'How can i insert parameter here from client..

            If con.State = ConnectionState.Closed Then
                con.Open()
            End If
            com.ExecuteNonQuery()
        End Using
    End Using
End Sub
End Class

如何在ExecuteNonQuery方法之前设置参数？

提前致谢..

Answer 1

我会做这样的事情：

Public Class SqlCommandManager
    Private m_SqlParameters As List(Of SqlParameter)
    Private m_Commandtext As String
    Private m_ConStr As String

    Public Sub New()
        m_SqlParameters = New List(Of SqlParameter)()
    End Sub

    Public ReadOnly Property SqlParameters() As List(Of SqlParameter)
        Get
            Return m_SqlParameters
        End Get
    End Property

    Public Property CommandText() As String
        Get
            Return m_Commandtext
        End Get
        Set
            value = m_Commandtext
        End Set
    End Property

    Public Sub New(con As String)
        m_ConStr = con
    End Sub

    Public Sub ExecuteNonQuery()
        Using con As New SqlConnection(m_ConStr)
            Using com As New SqlCommand(m_Commandtext, con)
                com.Parameters.AddRange(m_SqlParameters.ToArray())

                con.Open()
                com.ExecuteNonQuery()
                con.Close()
            End Using
        End Using
    End Sub
End Class

我改变了什么：

将班级名称更改为SqlCommandManager以符合Microsoft的建议（不要在缩写中大写超过2个字母; IO没问题，Sql和Xml不应全部大写）
我会使用List(Of SqlParameter)而不是数组 - 更容易处理，更容易添加其他参数
我更喜欢将CommandText和SqlConnection权限传递给SqlCommand的构造函数 - 这样，你绝对不会忘记这两个重要的信息！ / p>
在.ExecuteQuery之前，只需拨打SqlCommand
.AddRange()的参数数组中>

在VB.NET中设置SqlParameter？

1 个答案: