C # Notes For Calling C ++ Functions

I recently developed a client that interacts with hardware. The Development Kit is written in C ++. The client must be implemented in C #. I have encountered some problems during development, make yourself available for future reference.

 

1. Function Name: FPITemplate

2. function prototype

Int FPITemplage (int nPort, unsigned char * psMB, int * lpLength)

3. Function Description

The user enters the fingerprint three times, generates and uploads the fingerprint template.

4. Entry Parameters

NPort: Device Type

5. Exit Parameters

PsMB: the fingerprint template needs to allocate a buffer of 513 bytes.

LpLength: the fingerprint template consists of 512 bytes.

 

Define DLL Functions

         [DllImport(, EntryPoint =              FPITemplate( nPort,  _psMB,  lpLength);

Call in C #

        [] _psMB =   [ _lpLength = _psMB.Length -  i = FPITemplate(FPIDevDetect(), _psMB[], _lpLength);

In this way, fingerprint data can be obtained.

Read the returned byte fingerprint data

 FPI_Str =  (i == =

We hope this will help park friends and avoid detours.