How to call function and variables declared in other classes

Question

hi,

i have function stringconcat(a,b) in class1 with namespace s1 and want to call this function in class2.

 

i have written as given below and getting errors like 

Error 1 Cannot declare a variable of static type 's1.class1' 

Error 2 Cannot create an instance of the static class 's1.class1' 

 

Can someone please tell me what is wrong in this code

In file1.cs 

------------- 

namespace s1

{

publis static class class1

{ 

public static string a="IN";

public static string b="DIA"; 

public static void stringconcat(a,b);

}

}

In File2.cs 

---------------- 

namespace s1

{

publis static class class2

{

class1 class1=new class1(); 

class1.stringconcat(a,b);

}

}