在类中声明静态变量

Question

我在将Student命名为Student类中的静态变量时遇到错误。 任何人都可以帮我找到它。

class Student
    {
        public int SId;
        public string SName;
        public Student(int SId)
        {
            this.SId = SId;
            Console.WriteLine("Constructor is called");
        }
        static string coll = new string ();
        cool = "RVIM"

我收到以下错误。

Error   1   Invalid token '=' in class, struct, or interface member declaration C:\Users\amruthap\AppData\Local\Temporary Projects\ConsoleApplication1\Student.cs   18  14  ConsoleApplication1
Error   2   'string' does not contain a constructor that takes 0 arguments  C:\Users\amruthap\AppData\Local\Temporary Projects\ConsoleApplication1\Student.cs   17  37  ConsoleApplication1
Error   3   'ConsoleApplication1.Student.coll' is a 'field' but is used like a 'type'   C:\Users\amruthap\AppData\Local\Temporary Projects\ConsoleApplication1\Student.cs   18  9   ConsoleApplication1
    }

Answer 1

你不能调用默认的字符串构造函数 - String class没有ctor采用0参数..尝试将coll设置为“”

Answer 2

string不包含带0参数的构造函数

第二件事cool = "RVIM" =类结构或接口成员声明中的无效标记。

Answer 3

不要调用字符串构造函数...尝试将其视为值类型

static string coll =“”;