如果有些舊的VB6 的Code不想用人腦翻譯機把它翻成C#,
其實把舊的VB6 Code編成DLL來用,其實也蠻不錯的。
(1)首先開啟一個
ActiveX DLL 專案
(2)定義好你的Class名稱
(3)寫好(貼好)程式碼
Public Function Add(ByVal A As Double, ByVal B As Double) As Double
Dim sum As Double
c = A + B
Add = c
End Function
(4)編成DLL (如果VB6裝在WIN7以上,開啟VB IDE時記得用管理者,否則編譯會出錯)
(5)在VS2015裡引用這個DLL
(6)撰寫程式碼 ,一樣會出現Func提示
(7)完整程式碼如下
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace WindowsFormsApplication2
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
VBFunc.VB_dll mVB6_func = new VBFunc.VB_dll();
double sum = mVB6_func.Add(10.5, 1.8);
label1.Text = sum.ToString();
}
}
}
(8)執行結果
題外話
傳說中,VB6是原生的程式碼,會不會比C#快呢,
我們來試試看在C#與呼叫跟VB6 DLL的執行速度。
先來準備一個要RUN 1000000次的迴圈(執行環境為Win10 x64)
VB6 程式碼
Private Declare Function GetTickCount Lib "kernel32" () As Long
Private Sub Command1_Click()
Dim i As Long, temp As Long, temp1 As Long
temp = GetTickCount()
For i = 0 To 9
test
Next
temp1 = GetTickCount()
Form1.Print temp1 - temp & "ms"
End Sub
Public Function test() As Long
Dim sum As Long
For i = 0 To 1000000
sum = 1 + 2
Next
tst = 10
End Function
VB6 執行數次,大約都在110~140ms
C#程式碼
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace WindowsFormsApplication2
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
VBFunc.VB_dll mVB6_func = new VBFunc.VB_dll();
System.Diagnostics.Stopwatch sw = new System.Diagnostics.Stopwatch();
/*sw.Reset();
sw.Start();
for ( int i=0;i<10;i++)
{
long sum = mVB6_func.test();
}
sw.Stop();
string result1 = sw.Elapsed.TotalMilliseconds.ToString();
label1.Text = result1;*/
sw.Reset();
sw.Start();
for (int i = 0; i < 10; i++)
{
long sum = test();
}
sw.Stop();
string result2 = sw.Elapsed.TotalMilliseconds.ToString();
label2.Text = result2;
}
private long test()
{
long sum = 0;
for (long i = 0; i < 1000000; i++)
{
sum = 1 + 2;
}
return 10;
}
}
}
C# 只要60ms就執行完了。
有點怪異,VB6慢好多,是不是Win10不喜歡它。
我來做個嘗試,把VB6編成DLL,讓C# 呼叫看看
如果我把剛才那段程式碼編成DLL讓C#呼叫呢
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace WindowsFormsApplication2
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
Project1.Class1 class1 = new Project1.Class1();
System.Diagnostics.Stopwatch sw2 = new System.Diagnostics.Stopwatch();
sw2.Reset();
sw2.Start();
for (int i = 0; i < 10; i++)
{
long sum = test();
}
sw2.Stop();
string result2 = sw2.Elapsed.TotalMilliseconds.ToString();
label2.Text = "C# " + result2;
System.Diagnostics.Stopwatch sw = new System.Diagnostics.Stopwatch();
sw.Reset();
sw.Start();
for (int i = 0; i < 10; i++)
{
long sum = class1.test();
}
sw.Stop();
string result1 = sw.Elapsed.TotalMilliseconds.ToString();
label1.Text = "VB6 " + result1;
}
private long test()
{
long sum = 0;
for (long i = 0; i < 1000000; i++)
{
sum = 1 + 2;
}
return 10;
}
}
}
雖然執行變快了,但是VB6在執行這段程式碼,仍然比C慢上一些。