调用vc写的dll时出错，错误描述是：“Bad DLL calling convention”

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调用vc写的dll的某个方法时出错，错误描述是：“Bad DLL calling convention”
vc中方法名为：
void TV_OffHookCtrl (int iChannel,BOOL bStateSign=TRUE);
vb中声明为：
Private Declare Sub OffHookCtrl Lib "usbid.dll" Alias "TV_OffHookCtrl" (iChannel As Long)’
调用：
OffHookCtrl 1

各位高手，帮我看看问题出在哪里

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自己up一下

[zhysecond]

把声明改一下：
Private Declare Sub OffHookCtrl Lib "usbid.dll" Alias "TV_OffHookCtrl" (iChannel As Long,byval bStateSign as boolean)
调用改为：
offhookctrl 1,true

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Private Declare Sub OffHookCtrl Lib "usbid.dll" Alias "TV_OffHookCtrl" (iChannel As Long, Optional Byval bStateSign As Long = -1)

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还有这个调用也不知怎么弄。主要是想知道数据类型都怎么对应
int TV_StartDial (int iChannel, char far *Code,BOOL bStateSign=TRUE);

Private Declare Function StartDial Lib "usbid.dll" Alias "TV_StartDial" (iChannel As Long, ByRef code As String) As Integer

StartDial 1, txtPhone.Text

谢谢您的回复

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Private Declare Function StartDial Lib "usbid.dll" Alias "TV_StartDial" (ByVal iChannel As Long, ByRef code As String, Optional ByVal bStateSign As Long = -1) As long

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自己搞定了

[of123]

ByVal code As String