type TArr = array of TPoint; {把数组先定义成一个类型会方便许多, 这里仅用 TPoint 测试} {删除动态数组指定元素的过程: 参数 arr 是数组名, 参数 Index 是要删除的索引} procedure DeleteArrItem(var arr: TArr; Index: Integer); var Count: Cardinal; begin Count := Length(arr); if (Count = 0) or (Index < 0) or (Index >= Count) then Exit; Move(arr[Index+1], arr[Index], (Count-Index)* SizeOf(arr[0])); SetLength(arr, Count - 1); end; {测试} procedure TForm1.Button1Click(Sender: TObject); var arr: TArr; i: Integer; begin {测试数据} SetLength(arr, 5); arr[0].X := 1; arr[0].Y := 111; arr[1].X := 2; arr[1].Y := 222; arr[2].X := 3; arr[2].Y := 333; arr[3].X := 4; arr[3].Y := 444; arr[4].X := 5; arr[4].Y := 555; {删除第四个元素, 并查看删除后的结果} DeleteArrItem(arr, 3); for i := 0 to Length(arr) - 1 do Memo1.Lines.Add(Format(''%d, %d'', [arr[i].X, arr[i].Y])); end;
有时使用动态数组的指针更方便, 简单修改即可: type TArr = array of TPoint; PArr = ^TArr; {过程} procedure DeleteArrItem(p: PArr; Index: Integer); var Count: Cardinal; begin Count := Length(p^); if (Count = 0) or (Index < 0) or (Index >= Count) then Exit; Move(p^[Index+1], p^[Index], (Count-Index)* SizeOf(p^[0])); SetLength(p^, Count - 1); end; {测试} procedure TForm1.Button1Click(Sender: TObject); var arr: TArr; i: Integer; begin SetLength(arr, 5); arr[0].X := 1; arr[0].Y := 111; arr[1].X := 2; arr[1].Y := 222; arr[2].X := 3; arr[2].Y := 333; arr[3].X := 4; arr[3].Y := 444; arr[4].X := 5; arr[4].Y := 555; DeleteArrItem(@arr, 3); for i := 0 to Length(arr) - 1 do Memo1.Lines.Add(Format(''%d, %d'', [arr[i].X, arr[i].Y])); end; (责任编辑:admin)
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