E2235 Member function must be called or its address taken 怎么回事啊

[lmyanlong]

刚学 C++ builder，求帮助啊
编了这个程序，但运行时出现这个错误， 出现在 n=0 这一行
void __fastcall TForm1::FormKeyDown(TObject *Sender, WORD &Key,
TShiftState Shift)
{
if(ssShift==0)
{Repaint();
n=0; }
}
//---------------------------------------------------------------------------

void __fastcall TForm1::FormMouseDown(TObject *Sender, TMouseButton Button,
TShiftState Shift, int X, int Y)
{
int i,j;
if(mbLeft)
{
x[n]=X;
y[n]=Y;
n++;
Canvas->Pen->Color=clRed;
for(i=0;i<=n-2;i++)
for(j=i+1;j<=n-1;j++)
{Canvas->MoveTo(x[i],y[i]);
Canvas->LineTo(x[j],y[j]);
}
}
}

[lmyanlong]

int x[200],y[200];
int n=0;
数组x,y和n 在前面已经定义
求高手帮助啊

[new_BCBER]

在哪定义的？

[lmyanlong]

#include <vcl.h>
#pragma hdrstop

#include "ko3_3.h"
int x[200],y[200];
int n=0;
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
: TForm(Owner)
{
}
//---------------------------------------------------------------------------
void __fastcall TForm1::FormKeyDown(TObject *Sender, WORD &Key,
TShiftState Shift)
{
if(ssShift==0)
{Repaint();
n=0; }
}
错误发生在红字的n=0;
请指教啊