Question

我正在尝试创建一个屏幕截图并将其从C＃发送到我存储它的PHP。

我创建了这样的截图：

Bitmap screenshot = TakeScreenshot();

现在我尝试save it as a stream：

Stream myStream;  
screenshot.Save(myStream, System.Drawing.Imaging.ImageFormat.Gif);

但是，我得到Use of unassigned local variable 'myStream'。

我做错了什么？

功能

private Bitmap TakeScreenshot()
{
    //Create a new bitmap.
    var bmpScreenshot = new Bitmap(Screen.PrimaryScreen.Bounds.Width,
                                   Screen.PrimaryScreen.Bounds.Height,
                                   System.Drawing.Imaging.PixelFormat.Format32bppArgb);

    // Create a graphics object from the bitmap.
    using (var gfxScreenshot = Graphics.FromImage(bmpScreenshot))
    {    
        // Take the screenshot from the upper left corner to the right bottom corner.
        gfxScreenshot.CopyFromScreen(Screen.PrimaryScreen.Bounds.X,
                                Screen.PrimaryScreen.Bounds.Y,
                                0,
                                0,
                                Screen.PrimaryScreen.Bounds.Size,
                                CopyPixelOperation.SourceCopy);    
    }

    return bmpScreenshot;
}

Answer 1

Stream你的意思是FileStream，MemoryStream，是什么？无论如何，只需将变量初始化为您需要的适当类型的流。

例如：

using(var myStream = new MemoryStream())
{....}

Answer 2

您必须在使用之前初始化您的流。

using (MemoryStream myStream = new MemoryStream()) {
    screenshot.Save(myStream, System.Drawing.Imaging.ImageFormat.Gif);
}

如何将图像保存为流？

2 个答案: