VB 性能优化点
1.将Single,Double和Currency类型的变量替换为Integer或Long类型的变量;10倍
2.避免使用变体:
慢:Dim FSO as object Set FSO = New Scripting.FileSystemObject
快:Dim FSO as New FileSystemObject
3.值处理时使用变量而不使用属性,尤其是在循环中;20倍
慢:Text1.Text = Text1.Text & vbcrlf & SomeVar(intCon)
快:sOutput = sOutput & vbCrlf & SomeVar(intCon) Text1.Text = sOutput
4.尽量使用数组替代集合;100倍
5.展开小的循环体;
6.不使用很短的函数;
7.使用With:
With frmMain.Text1
.Text = "Learn VB"
.Alignment = 0
.Tag = "Its my life"
.BackColor = vbBlack
.ForeColor = vbWhite
End With
只适用于需要对一个对象的子对象进行操作的时候,下面这
段代码是不正确的:
With Text1
.Text = "Learn VB"
.Alignment = 0
.Tag = "Its my life"
.BackColor = vbBlack
.ForeColor = vbWhite
End With
8.检查字符串是否为空:
慢:If Text1.Text = "" then
快:If Len(Text1.Text) = 0 then
9.使用动态数组,而不是静态数组,节约资源;
10.销毁对象:Dim FSO as New FileSystemObject Set FSO = Nothing;
11.使用对象数组;
12.使用Move方法:
慢:
Image1.Width = 100
Image1.Height = 100
Image1.Top = 0
Image1.Left = 0
快:
Image1.Move 0,0,100,100