Add和AddRange区别

Add和AddRange

Add：将指定的对象添加到……中

AddRange：向……末尾，添加数组

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在群体操作时，使用AddRange取代Add

用AddRange可以让我们要加入的东西一次性加入，而不要每次都加一次，这样显然可以加快速度。几乎所有的windows control都支持Add和AddRange两种方法。

Add:

For i = 0 To param.Length - 1
        comm.Parameters.Add(param(i))
Next i

 

AddRange:

Comm.Parameters.AddRange(Param)

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支持Add和AddRange的类：
StringCollection, TraceCollection, SqlParameter, etc.
HttpWebRequest
UserControl
ColumnHeader

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原代码：

''' ExecuteQuery,查询数据操作
''' </summary>
''' <param name="strSql">sql语句</param>
''' <param name="param">参数集合</param>
''' <param name="ct">命令类型</param>
''' <returns>DataTable类型，数据表</returns>
''' <remarks></remarks>
Public Function ExecuteQuery(ByVal strSql As String, ByVal param() As SqlParameter, ByVal ct As CommandType) As DataTable
    Dim dt As New DataTable

    comm = New SqlCommand(strSql, Me.GetConn)
    comm.CommandType = ct

    If param IsNot Nothing Then
        For i = 0 To param.Length - 1
            comm.Parameters.Add(param(i))
        Next i
    End If

    Try
        dr = comm.ExecuteReader()
        dt.Load(dr)
    Catch ex As Exception
        Throw ex
    Finally
        dr.Close()
        conn.Close()
    End Try

    Return dt
End Function

修改后：

''' <summary>
''' 查询方法
''' </summary>
''' <param name="myCommandType">sql语句类型:区别于存储过程</param>
''' <param name="Param">参数数组</param>
''' <param name="strSql">sql语句</param>
Public Function ExecuteQuery(ByVal myCommandType As CommandType, ByVal Param() As SqlParameter, ByVal strSql As String) As DataTable
    Dim dt As New DataTable

    Comm = New SqlCommand(strSql, Me.GetConn)
    Comm.CommandType = myCommandType

    If Param IsNot Nothing Then
        Comm.Parameters.AddRange(Param)
    End If

    Try
        myDataReader = Comm.ExecuteReader
        dt.Load(myDataReader)
    Catch ex As Exception
        Throw ex
    Finally
        myDataReader.Close()
        Conn.Close()
    End Try

    Return dt
End Function