Question

在我的WPF中，我创建了一个名为“ image_box”的图像框

在Window_Loaded上，我用

加载我的图像框

image_box.Source = new BitmapImage(new Uri("pack://application:,,,/images/pic.png"));

我在Rotate_Click（对象发送者，RoutedEventArgs e）上有下一个代码

BitmapImage bmp = new BitmapImage();
bmp.BeginInit();
bmp.UriSource = new Uri("pack://application:,,,/images/pic.png");
bmp.EndInit();

TransformedBitmap myRotatedBitmapSource = new TransformedBitmap();
myRotatedBitmapSource.BeginInit();
myRotatedBitmapSource.Source = bmp;
myRotatedBitmapSource.Transform = new RotateTransform(90);
myRotatedBitmapSource.EndInit();
image_box.Source = myRotatedBitmapSource;

我想要的是这段代码

bmp.UriSource =新的Uri（“ pack：// application：,,, / images / pic.png”）;

使用

image_box的位置

bmp.UriSource = image_box.Source;

我尝试

Uri ur = new Uri(image_box.Source.ToString());
...
bmp.UriSource = ur;

但在第二次点击我得到无效的网址

Answer 1

表达式

image_box.Source.ToString()

仅在Source是BitmapImage时返回有效的URI字符串。但是，在您的Click处理程序的第二次调用中，Source是TransformedBitmap。

您应该简单地重用原始源图像并将旋转角度增加（或减小）90的倍数。

private BitmapImage source = new BitmapImage(new Uri("pack://application:,,,/images/pic.png"));
private double rotation = 0;

private void Rotate_Click(object sender, RoutedEventArgs e)
{
    rotation += 90;
    image_box.Source = new TransformedBitmap(source, new RotateTransform(rotation));
}

或者也保留TransformedBitmap并仅更改其Transform属性：

private BitmapImage source = new BitmapImage(new Uri("pack://application:,,,/images/pic.png"));
private double rotation = 0;
private TransformedBitmap transformedBitmap =
    new TransformedBitmap(source, new RotateTransform(rotation));
...
image_box.Source = transformedBitmap; // call this once
...

private void Rotate_Click(object sender, RoutedEventArgs e)
{
    rotation += 90;
    transformedBitmap.Transform = new RotateTransform(rotation);
}

wpf使用bitmapimage作为TransformedBitmap的源

1 个答案: