关于调用delphi写的DLL的问题，纠结啊
delphi的接口方法是这样的：
procedure GetLastCashCardBalance(Card:PTMemberCashCard_Rd);stdcall;
begin
Card.iMemberID := FPosService.LastCashCardBalance.iMemberID;
SetPChar(@Card.sMemberCode[0], FPosService.LastCashCardBalance.sMemberCode);
DateTimeToSystemTime(FPosService.LastCashCardBalance.dateValid,Card.dateValid);
Card.mBalance := FPosService.LastCashCardBalance.mBalance;
Card.mBottom := FPosService.LastCashCardBalance.mBottom;
Card.mAmount := FPosService.LastCashCardBalance.mAmount;
end;
其中PTMemberCashCard_Rd是这么定义的
{ TMemberCashCard = class
iMemberID: integer;
sMemberCode: string;
dateValid: TDate;
mBalance: TMoney;
mBottom: TMoney;
mAmount: TMoney;
bRecycle: boolean;
public
procedure Clear;
end; }

TMemberCashCard_Rd = Record
iMemberID: integer;
sMemberCode: Array[0..255] of char;
dateValid: SystemTime;
mBalance: integer;
mBottom: integer;
mAmount: integer;
bRecycle: Integer;
end;

PTMemberCashCard_Rd =^TMemberCashCard_Rd;

我在C#里的调用方法如下
定义结构
public struct LastCashCardBalance
{
public Int32 iMemberID;
public string sMemberCode;
public DateTime dateValid;
public Int32 mBalance;
public Int32 mBottom;
public Int32 mAmount;
public Int32 bRecycle;
}

[DllImport("CardInterface.dll", CallingConvention = CallingConvention.StdCall, CharSet = CharSet.Ansi)]
public static extern void GetLastCashCardBalance( LastCashCardBalance s);

调用：
LastCashCardBalance lst = new LastCashCardBalance();
GetLastCashCardBalance(lst);
提示尝试读取或写入受保护的内存。这通常指示其他内存已损坏。求大侠帮忙看看是什么原因啊

[解决办法]
传参错误 要指针类型
[解决办法]
ref LastCashCardBalance s

另外delphi中不要用string类型，改为array of byte 或 array of char