C # static field and instance field analysis

C # language has a lot to learn, here we mainly introduce C # static fields and C # instance fields, including the introduction of the ReadOnly keyword is used to fame a read-only field.

C # static fields and C # instance fields

Fields have C # static fields and C # instance fields two, which are reference-passing and can be of any type.

Cases:

private　static　int　i　=　0;　　//声名一个静态字段
private　int　j　=　0;　　//声名一个实例字段
static　void　Main(string[]　args)
{
Program　a　=　new　Program();//建立对像引用，并实例化。
Console.WriteLine(a.j);//用对像来访问字段j
Console.WriteLine(Program.i);//静态字段需要用类名来访问
}

As we can see from the example, the static field belongs to the class, and the instance field belongs to the object.

ReadOnly Key Words:

The ReadOnly keyword is used to name a read-only field, which means that the field is not allowed to be overwritten, except that, in a constructor, a read-only field can be overwritten.

Cases:

class　Program
{

private　readonly　int　i　=　0;//声名一个只读字段
private　readonly　int　j　=　0;
Program()
{
this.j　=　10;//构造函数中对字段j进行改写
}

static　void　Main(string[]　args)
{

Program　a　=　new　Program();//建立对像引用，并实例化。
//a.i　=　10;//这里是会报错的
Console.WriteLine(a.j);
Console.WriteLine(a.i);
}
}