为什么当前上下文中不存在名称pictureBox1？

做一个图片编辑器，内容是选择图片，水平翻转，垂直翻转，但是显是当前上下文中不存在openFileDialog、pictureBox1
加了//OpenFileDialog openFileDialogl = new OpenFileDialog();
           //pictureBox pictureBox1=new pictureBox();
仍然不能用。
 问题在哪？


代码
private void button1_Click(object sender, EventArgs e)
        {
           //OpenFileDialog openFileDialogl = new OpenFileDialog();
           //pictureBox pictureBox1=new pictureBox();
            openFileDialog.Filter ="*.jpg,*.jpeg,*.bmp,*.gif,*.ico,*.png,*.tif,*.wmf|*.jpg;*.jpeg;*.bmp;*.gif;*.ico;*.png;*.tif;*.wmf";
            if(openFileDialog,ShowDialog()==DialogResult.OK);
            {
                Image myImage=System.Drawing.Image.FromFile (openFileDialog1.FileName);
                pictureBox1.Image=myImage ;
                pictureBox1.Height=myImage .Height ;
                pictureBox1.Width=myImage .Width ;
            }
        }
        //垂直翻转
        private void button2_Click(object sender, EventArgs e)
        {
            Image myImage = pictureBox1.Image;
            myImage.RotateFlip(RotateFlipType.Rotate180FlipNone);
            pictureBox1.iMAGE = myImage;
        }

        //水平翻转
        private void button1_Click_1(object sender, EventArgs e)
        {
            Image myImage = pictureBox1.Image;
            myImage .RotateFlip(RotateFlipType.Rotate90FlipNone)//水平翻转
                pictureBox1.Image=myImage ;
        }