AddRange 取代 Add

cmd.Parameters的Add方法是增加一个参数,增加多个参数的的时候使用一个foreach循环，cmd.Parameters的AddRange方法是增加一个参数的数组。

Add：将指定的对象添加到……中

AddRange：向……末尾，添加数组

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，而不要每次只加一个，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)

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

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

''' 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