c# - 在 C# 中使用 RotateFlip 旋转图像

Question

我有这段代码可以在 C# Windows 窗体应用程序的 if 循环中旋转图像，但窗体在窗体输出中不显示任何内容。

任何人都可以帮忙吗？

this.splitContainer1.Panel2.Controls.Add(PictureBox1);
PictureBox1.SizeMode = PictureBoxSizeMode.AutoSize;
PictureBox1.Image = bitmap; //Image.FromFile(@"C:\image.jpg");
PictureBox1.SizeMode = PictureBoxSizeMode.AutoSize;
PictureBox1.Image = (Image)(RotateImg(bitmap, 30.0f, Color.Transparent));

Answer 1

if you need to rotate an image on common angles you can use RotateFlip method with ease. Please see my sample code:

string fileName = "somefile.png";
System.Drawing.Imaging.ImageFormat imageFormat = System.Drawing.Imaging.ImageFormat.Png;
Bitmap bitmap =(Bitmap)Bitmap.FromFile(fileName );
//this will rotate image to the left...
bitmap.RotateFlip(RotateFlipType.Rotate270FlipNone);
//lets save result back to file...
bitmap.Save(fileName, imageFormat);
bitmap.Dispose();

That's all, hope it helps.

Answer 2

尝试这个：

PictureBox1.Images.RotateFlip(RotateFlipType.Rotate180FlipX);
PictureBox1.Refresh();