编程为何出错？各位大虾帮忙啊！

procedure TImageForm.FileListBox1Change(Sender: TObject);
var
  FileExt:string[4];
  Caption:string;{（此处定义）}
begin
  FileExt:=ExtractFileExt(FileListBox1.FileName);
  if(FileExt='.bmp') or (FileExt='.ico') then
  begin
    Image1.picture.loadFromFile(FileListBox1.FileName);
    Caption:=FormCaption+ExtractFileName(FileListBox1.FileName);{(此处提示有错误）这里FormCaption会不会是Form.Caption?另外，这段代码是在窗体代码中的吧，Caption会不会与Form.Caption有冲突？而且TForm自己本身有Caption这个property,还用你定义吗？}
    if(FileExt='.bmp')then
    begin
      Caption:=Caption+Format('%d*%d),
{这里，字符串符''没有结束，缺右边的，却多了一个右括号}
[Image1.Picture.Width,Image1.Picture.Height);
{^^^^前面的[多余}
      ViewForm.Image1.Picture:=Image1.Picture;
      ViewForm.Caption:=Caption;
    end
    if(FileExt='.ico')then Icon:=Image1.Picture.Icon;
  end
  else if(FileExt='.jpg) then
  begin
  JpgImage.LoadFromFile(FileListBox1.FileName);
  Image1.Picture.Graphic:=JpgImage;
  Caption:=FormCaption+ExtractFileName(FileListBox1.FileName);
  Caption:=Caption+ Format(%d*%d),[Image1.Picture.Width,Image1.Picture.Height);
{                      ^^^^^^^^^^^^^^^^^^^^^^^^上面！同样的错误}
  ViewForm.Image1.Picture.Graphic:=JpgImage;
  ViewForm.Image1.Caption:=Caption;
  end
end