(1)用C++builder6调用DLL
用VC2015创建包含MFC库的DLL,如果是给C++Builder6使用，步骤如下:
1、工程属性==》C++==》高级==》调用约定 选项为：__stdcall (/Gd)
2、VC++2015中的函数声明如下：
extern "C" __declspec(dllexport) VOID __stdcall CreateMeter(const char* szTypeName);
3.VC++2015的def文件,EXPORTS可以不用写，因为C++Builder6不用到这个.lib文件
不过,我发现要导出函数,需要在def字声明,否则在其他语言中找不到函数,提示错误.
4.在C++Builder6中,需要重新导出DLL的引导库.lib，方法如下：
implib my.lib my.dll
在BCB6工程中引入my.lib，同时添加函数声明，也就是VC2015DLL中的函数声明(与第2步相同)
(2)用Delphi7调用
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
|
unit
ScaleWeight_dll;
interface
procedure
CreateMeter(xktype:
PChar
;
No:
integer
;
Comm:
integer
;
baud:
integer
;
parity:
Char
;
databit:
integer
;
stopbit:
integer
);stdcall;external
'YuComm.dll'
;
//获取重量字符串
function
GetWeight( buff :
pchar
;index :
integer
=
1
):
PChar
;stdcall;
external
'YuComm.dll'
;
//写串口
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';
//辅助函数
//缓取缓冲区数据量
function
GetBuffLength(index :
integer
=
0
):
integer
;stdcall;
external
'YuComm.dll'
;
//或取通信状态；true串口打开但通信中断，false通信正常
function
GetStatus(index :
integer
=
0
):
boolean
;stdcall;external
'YuComm.dll'
;
//清除缓冲区数据
//procedure Clear(index :integer =0);stdcall;external 'YuComm.dll';
//获取原始数据
function
GetSourceData( buff :pbyte;index :
integer
=
0
):
integer
;stdcall;
external
'YuComm.dll'
;
implementation
end
.
|
将上面文件保存为扩展名为pas的文件,添加到delphi7工程中.
(3)在VB6中调用DLL
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
|
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
'需要添加一个返回值声明,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 =
"串口打开成功"
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平台下,用VB6调用,请用release方式编译,否则VB6会提示找不到相应的DLL文件,即所这个文件就在运行目录下
在VB中调用,声明函数时应加上返回值,即使DLL中这个函数没有返回值.返回值的类型可任意
(4)在C#中调用DLL
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
|
public
partial
class
Form1 : Form
{
//========================================================================
//1、创建仪表，并打开仪
[DllImport(
"YuComm.dll"
)]
public
static
extern
bool
CreateMeter(
string
xktype,
int
no,
int
comm,
int
baud,
int
parity,
int
databit,
int
stopbit);
//2、读取仪表重量，多台仪表时，参数为索引
[DllImport(
"YuComm.dll"
)]
public
static
extern
string
GetWeight(StringBuilder weight,
int
index = 1);
//写串口
[DllImport(
"YuComm.dll"
)]
public
static
extern
void
Write(
ref
byte
buff,
int
index = 1);
//3、关闭串口
[DllImport(
"YuComm.dll"
)]
public
static
extern
void
ClosePort(
int
index=1);
//ScaleWeight辅助功能函数：获取缓冲区数据个数
[DllImport(
"YuComm.dll"
)]
public
static
extern
int
GetBuffLength(
int
index = 1);
//获取通信状态：false通信正常 ，true通信中断
[DllImport(
"YuComm.dll"
)]
public
static
extern
bool
GetStatus(
int
index=1);
//辅助功能函数：读取原始数据流
[DllImport(
"YuComm.dll"
)]
public
static
extern
int
GetSourceData(
ref
byte
buff,
int
index = 1);
//辅助功能函数：清除缓冲区
//[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 =
"串口状态：打开成功"
;
}
else
{
label1.Text =
"串口状态：打开不成功"
;
}
}
private
void
button2_Click(
object
sender, EventArgs e)
{
ClosePort(1);
label1.Text =
"串口状态：串口关闭"
;
}
private
void
timer1_Tick(
object
sender, EventArgs e)
{
StringBuilder buff =
new
StringBuilder(255);
GetWeight(buff,1);
label2.Text = buff.ToString();
buff =
null
;
//释放
label5.Text =
"缓冲区中数据量："
+ GetBuffLength().ToString();
bool
re = GetStatus();
if
(re)
label4.Text =
"通信状态：通信数据流正常"
;
else
label4.Text =
"通信状态：通信数据流中断"
;
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 =
"暂停"
;
else
button4.Text =
"开始"
;
}
}
|
在XP上运行,请使用release方式编译发布,否则调用DLL中的函数时会报错!
本文转自Chinayu201451CTO博客，原文链接：http://blog.51cto.com/9233403/2063081 ，如需转载请自行联系原作者
