问如何在picturebox c#中对齐来自文本输入的绘图字符串bmp

EN

    private void button18_Click(object sender, EventArgs e)
    {
        //dispose previous image
        File.Delete("myimage.bmp");

        // Our text to paint
        String str = textBox1.Text;

        // Create our new bitmap object
        Bitmap bmp = new Bitmap(96,64);
        Image img = Image.FromHbitmap(bmp.GetHbitmap());

        // Get our graphics object
        Graphics g = Graphics.FromImage(img);
        g.Clear(Color.Transparent);

        // Define our image padding
        var imgPadding = new Rectangle(1, 1, 1, 1);

        // Determine the size of our text, using our specified font.
        Font ourFont = new Font(
            FontFamily.GenericSansSerif,
            10.0f,
            FontStyle.Regular,
            GraphicsUnit.Point
        );
        SizeF strSize = g.MeasureString(
            str,
            ourFont,
            (bmp.Width - imgPadding.Left - imgPadding.Right),
            StringFormat.GenericDefault
        );
        // Create a StringFormat object with the each line of text, and the block
        // of text centered on the page.
        StringFormat stringFormat = new StringFormat();
        stringFormat.Alignment = StringAlignment.Center;
        stringFormat.LineAlignment = StringAlignment.Center;

        // Create our brushes
        SolidBrush textBrush = new SolidBrush(Color.White);

        // Draw our string to the bitmap using our graphics object
        g.DrawString(str, ourFont, textBrush, imgPadding.Left, imgPadding.Top, stringFormat);

        // Flush
        g.Flush(System.Drawing.Drawing2D.FlushIntention.Sync);

        // Save our image.
        img.Save("myImage.bmp", System.Drawing.Imaging.ImageFormat.Bmp);

        // Clean up
        textBrush.Dispose();
        g.Dispose();
        bmp.Dispose();

        //showimageon screen
        Image img1;
        using (var bmpTemp = new Bitmap("myImage.bmp"))
        {
            img1 = new Bitmap(bmpTemp);
        }
        pictureBox4.Image = img1;