c# - 为什么位图保存为PNG

Question

我的应用程序中有位图对象。为什么Save()方法保存的是PNG格式的文件而不是BMP？

Bitmap currentImmage;
...
currentImmage.Save("image.bmp");

Answer 1

来自文档

Save(String)

If no encoder exists for the file format of the image, the Portable Network Graphics (PNG) encoder is used. When you use the Save method to save a graphic image as a Windows Metafile Format (WMF) or Enhanced Metafile Format (EMF) file, the resulting file is saved as a Portable Network Graphics (PNG) file. This behavior occurs because the GDI+ component of the .NET Framework does not have an encoder that you can use to save files as .wmf or .emf files.

改用

Save(String, ImageFormat)

Saves this Image to the specified file in the specified format.

ImageFormat Class

Specifies the file format of the image.

示例

currentImmage.Save("image.bmp",ImageFormat.Bmp);