Question

我有两种方法：一种处理更新图片，一种调整图片大小并绘制一个矩形。

public void updatePicture()
{
    if (imageList.SelectedItem == null) return;

    /*String fileName = imageList.SelectedItem.ToString();
    var currentFile = new System.IO.FileInfo(imageList.SelectedItem.ToString());

    pictureBox1.Load(fileName); This code is moved to resizeImage*/

    resizeImage(false, true);
    //drawRect(); It works if I enable this code
}

但是，我试图将所有内容移到resizeImage（）：

private void resizeImage(Boolean draw, Boolean update)
{
    if (!isValid()) return;

    if (update) 
    {
        String fileName = imageList.SelectedItem.ToString();
        var currentFile = new System.IO.FileInfo(imageList.SelectedItem.ToString());
        pictureBox1.Load(fileName);
    }

    Bitmap bitmap = new Bitmap(pictureBox1.Image);

    if (bitmap.Width < pictureBox1.Width && bitmap.Height < pictureBox1.Height)
    {
        pictureBox1.Image = bitmap;
        return;
    }

    int width, height;

    float percentWidth = (float)pictureBox1.Width / (float)bitmap.Width;
    float percentHeight = (float)pictureBox1.Height / (float)bitmap.Height;
    float percent = percentHeight < percentWidth ? percentHeight : percentWidth;

    width = Convert.ToInt32(bitmap.Width * percent);
    height = Convert.ToInt32(bitmap.Height * percent);

    Bitmap cropBitmap = new Bitmap(width, height);
    Graphics g = Graphics.FromImage(cropBitmap);

    g.CompositingQuality = System.Drawing.Drawing2D.CompositingQuality.HighQuality;
    g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;
    g.PixelOffsetMode = System.Drawing.Drawing2D.PixelOffsetMode.HighQuality;
    g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;

    g.DrawImage(bitmap, 0, 0, cropBitmap.Width, cropBitmap.Height);
    pictureBox1.Image = cropBitmap;

    if (draw) 
    {
        drawRect();
    }
}

在这种状态下它不会工作，但为了使它工作，我只需在updatePicture（）方法中调用drawRect（）方法，这基本上只是移动代码。我也不是在不同时间打电话。

这是我的drawRect（）方法：

private void drawRect()
{
    pictureBox1.Refresh();
    pictureBox1.CreateGraphics().DrawRectangle(pen, cropX, cropY, cropW, cropH);
}

任何人都能看到我的错误？

Answer 1

也许这有帮助？

    if (bitmap.Width < pictureBox1.Width && bitmap.Height < pictureBox1.Height)
    {

        pictureBox1.Image = bitmap;

        // add this line...
        pictureBox1.Refresh();

        return;
    }

也许还低于......

    pictureBox1.Image = cropBitmap;
    // add this line...
    pictureBox1.Refresh();

也许你看到我在做什么......在所有情况下都要调用刷新。

Answer 2

        if (bitmap.Width < pictureBox1.Width && bitmap.Height < pictureBox1.Height)
    {

        pictureBox1.Image = bitmap;

        return;
    }

如果语句为真，则该代码返回，并且不会绘制。

我将resizeImage方法更改为：

        private void resizeImage(Boolean draw, Boolean update)
    {

        if (!isValid()) return;

        if (update) 
        {

            String fileName = imageList.SelectedItem.ToString();
            var currentFile = new System.IO.FileInfo(imageList.SelectedItem.ToString());

            pictureBox1.Load(fileName);

        }

        Bitmap bitmap = new Bitmap(pictureBox1.Image);
        bool needsCrop = true;

        if (bitmap.Width < pictureBox1.Width && bitmap.Height < pictureBox1.Height)
        {

            pictureBox1.Image = bitmap;
            needsCrop = false;

        }

        if (needsCrop)
        {

            int width, height;

            float percentWidth = (float)pictureBox1.Width / (float)bitmap.Width;
            float percentHeight = (float)pictureBox1.Height / (float)bitmap.Height;
            float percent = percentHeight < percentWidth ? percentHeight : percentWidth;

            width = Convert.ToInt32(bitmap.Width * percent);
            height = Convert.ToInt32(bitmap.Height * percent);

            Bitmap cropBitmap = new Bitmap(width, height);
            Graphics g = Graphics.FromImage(cropBitmap);

            g.CompositingQuality = System.Drawing.Drawing2D.CompositingQuality.HighQuality;
            g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;
            g.PixelOffsetMode = System.Drawing.Drawing2D.PixelOffsetMode.HighQuality;
            g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;

            g.DrawImage(bitmap, 0, 0, cropBitmap.Width, cropBitmap.Height);
            pictureBox1.Image = cropBitmap;

        }

        if (draw) { drawRect(); }
    }

抱歉浪费你的时间：/

重构两个函数失败

2 个答案: