C + + prototype function: int f_UserBargaingClose (const char * Data, char * retMsg, char * Data2)

C # call static extern int f_UserBargaingInit (string lpData1, ref string lpMessage, string lpData2);

When call to get a return value because it is over, so a ref returns lpMessage, running time is submitted to the System. "ExecutionEngineException" type of untreated exception error, who can instruct me,
After test if you don't add the ref can perform successfully, return int return value of the function itself,
Don't tell I have to do is remove the ref, etc.,,,, call this function is to get the meaning of lpMessage

CodePudding user response:

Returns the parameters of the use StringBuilder sb1=new StringBuilder (512); Have a try