What is the difference between System.Drawing.Image and System.Drawing.Bitmap?

Question

I am confused what's the different between System.Drawing.Image and System.Drawing.Bitmap

Can someone explain the major difference between those two types ?

为什么要使用System.Drawing.Bitmap而不是System.Drawing.Image？

Answer 1

Bitmap继承自Image:

System.Drawing.Bitmap : System.Drawing.Image
{ }

Image 是一个抽象类,这意味着:

abstract修饰符指示正在修改的事物具有缺失或不完整的实现.

Bitmap 是一个密封的类,这意味着:

应用于类时,sealed修饰符会阻止其他类继承它.

请参阅以下内容:

Bitmap bmp = new Bitmap(filename); // Works
Image img = new Image(); // The compiler says: "Cannot access internal constructer 'Image' here.

这是因为Image不打算以这种方式使用.它只是为Bitmap类提供功能.

因此总是使用Bitmap而不是Image.