(1)用C++builder6調(diào)用DLL
用VC2015創(chuàng)建包含MFC庫的DLL,如果是給C++Builder6使用，步驟如下:
1、工程屬性==》C++==》高級==》調(diào)用約定 選項為：__stdcall (/Gd)
2、VC++2015中的函數(shù)聲明如下：
extern "C" __declspec(dllexport) VOID __stdcall CreateMeter(const char* szTypeName);
3.VC++2015的def文件,EXPORTS可以不用寫，因為C++Builder6不用到這個.lib文件
不過,我發(fā)現(xiàn)要導(dǎo)出函數(shù),需要在def字聲明,否則在其他語言中找不到函數(shù),提示錯誤.
4.在C++Builder6中,需要重新導(dǎo)出DLL的引導(dǎo)庫.lib，方法如下：
implib my.lib my.dll
在BCB6工程中引入my.lib，同時添加函數(shù)聲明，也就是VC2015DLL中的函數(shù)聲明(與第2步相同)
(2)用Delphi7調(diào)用
unit ScaleWeight_dll; interface procedure CreateMeter(xktype:PChar; No:integer; Comm:integer; baud:integer; parity:Char; databit:integer; stopbit:integer );stdcall;external 'YuComm.dll'; //獲取重量字符串 function GetWeight( buff :pchar;index :integer = 1):PChar;stdcall; external 'YuComm.dll'; //寫串口 procedure WritePort( buff :array of byte;index :integer = 0);stdcall; external 'YuComm.dll'; function ClosePort(index :integer=1):integer;stdcall;external 'YuComm.dll'; //name 'ClosePort1'; //輔助函數(shù) //緩取緩沖區(qū)數(shù)據(jù)量 function GetBuffLength(index :integer =0):integer;stdcall; external 'YuComm.dll'; //或取通信狀態(tài)；true串口打開但通信中斷，false通信正常 function GetStatus(index :integer =0):boolean;stdcall;external 'YuComm.dll'; //清除緩沖區(qū)數(shù)據(jù) //procedure Clear(index :integer =0);stdcall;external 'YuComm.dll'; //獲取原始數(shù)據(jù) function GetSourceData( buff :pbyte;index :integer = 0):integer;stdcall; external 'YuComm.dll'; implementation end.
將上面文件保存為擴(kuò)展名為pas的文件,添加到delphi7工程中.
(3)在VB6中調(diào)用DLL
Private Declare Function CreateMeter Lib "YuComm"(ByVal name As String, _ ByVal No As Integer, _ ByVal port As Integer, _ ByVal baud As Integer, _ ByVal parity As Integer, _ ByVal databit As Integer, _ ByVal stopbit As Integer) As Boolean'需要添加一個返回值聲明,即使不需要 Private Declare Function GetWeight Lib "YuComm"(ByVal buff As String, Optional ByVal index As Integer = 1) As Long Private Declare Function GetStatus Lib "YuComm"(Optional ByVal index As Integer = 1) As Integer Private Declare Function ClosePort Lib "YuComm"(Optional ByVal index As Integer = 1) As Boolean Private Sub Command1_Click() Dim name As String Dim port As Integer Dim baud As Integer name = Combo1.Text port = CInt(Text1.Text) baud = CInt(Text2.Text) CreateMeter name, 1, port, baud, 110, 8, 1 End Sub Private Sub Command2_Click() ClosePort (1) End Sub Private Sub Command3_Click() End Sub Private Sub Timer1_Timer() Dim re As Boolean re = GetStatus(1) If re = True Then Label2.Caption = "串口打開成功" Else Label2.Caption = "串口打不成功" End If Dim buff1 As String buff1 = Space(100) Call GetWeight(buff1, 1) Label1.Caption = buff1 End Sub
在XP平臺下,用VB6調(diào)用,請用release方式編譯,否則VB6會提示找不到相應(yīng)的DLL文件,即所這個文件就在運(yùn)行目錄下
在VB中調(diào)用,聲明函數(shù)時應(yīng)加上返回值,即使DLL中這個函數(shù)沒有返回值.返回值的類型可任意
(4)在C#中調(diào)用DLL
重慶分公司
重慶分公司
public partial class Form1 : Form
{
//========================================================================
//1、創(chuàng)建儀表，并打開儀
[DllImport("YuComm.dll")]
public static extern bool CreateMeter(string xktype,int no,int comm,
int baud,int parity,int databit,int stopbit);
//2、讀取儀表重量，多臺儀表時，參數(shù)為索引
[DllImport("YuComm.dll")]
public static extern string GetWeight(StringBuilder weight, int index = 1);
//寫串口
[DllImport("YuComm.dll")]
public static extern void Write(ref byte buff,int index = 1);
//3、關(guān)閉串口
[DllImport("YuComm.dll")]
public static extern void ClosePort( int index=1);
//ScaleWeight輔助功能函數(shù)：獲取緩沖區(qū)數(shù)據(jù)個數(shù)
[DllImport("YuComm.dll")]
public static extern int GetBuffLength(int index = 1);
//獲取通信狀態(tài)：false通信正常 ，true通信中斷
[DllImport("YuComm.dll")]
public static extern bool GetStatus(int index=1);
//輔助功能函數(shù)：讀取原始數(shù)據(jù)流
[DllImport("YuComm.dll")]
public static extern int GetSourceData(ref byte buff, int index = 1);
//輔助功能函數(shù)：清除緩沖區(qū)
//[DllImport("YuComm.dll")]
//public static extern void Clear(int index=1);
//===================================================================
public Form1()
{
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
xktype = comboBox1.Text;
szComm = textBox1.Text;
szBaud = textBox2.Text;
bool re = CreateMeter(xktype, 1, Convert.ToInt32(szComm),
Convert.ToInt32(szBaud), 'n', 8, 1);
if (re)
{
label1.Text = "串口狀態(tài)：打開成功";
}
else
{
label1.Text = "串口狀態(tài)：打開不成功";
}
}
private void button2_Click(object sender, EventArgs e)
{
ClosePort(1);
label1.Text = "串口狀態(tài)：串口關(guān)閉";
}
private void timer1_Tick(object sender, EventArgs e)
{
StringBuilder buff = new StringBuilder(255);
GetWeight(buff,1);
label2.Text = buff.ToString();
buff = null;//釋放
label5.Text = "緩沖區(qū)中數(shù)據(jù)量："+ GetBuffLength().ToString();
bool re = GetStatus();
if (re)
label4.Text = "通信狀態(tài)：通信數(shù)據(jù)流正常";
else
label4.Text = "通信狀態(tài)：通信數(shù)據(jù)流中斷";
byte[] data = new byte[1024];
int c = GetSourceData(ref data[0],1);
richTextBox1.Clear();
for (int i = 0; i < c; i++)
{
richTextBox1.Text += data[i].ToString("X2") +" ";
}
data = null;
}
private void button3_Click(object sender, EventArgs e)
{
byte[] buff = new byte[1024];
string a = "hello";
BitConverter.ToString(buff);
Write(ref buff[0], 1);
buff = null;
}
private void button4_Click(object sender, EventArgs e)
{
timer1.Enabled = !timer1.Enabled;
if (timer1.Enabled)
button4.Text = "暫停";
else
button4.Text = "開始";
}
}在XP上運(yùn)行,請使用release方式編譯發(fā)布,否則調(diào)用DLL中的函數(shù)時會報錯!
