Add和AddRange的区别

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

AddRange:

Comm.Parameters.AddRange(Param)

-

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

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原代码：

view plain
.''' 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 =  To param.Length -
.            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：

view plain
.''' <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