using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace abc
{
public class Class1
{
public void display()
{
Console.WriteLine("Hallo");
}
public static void main(string[] args)
{
Class1 obj = new Class1();
obj.display();
}
}
}
I have created one static method and called in main method to check how dll converted to exe work .

The entry point needs to be called Main, not main.
That's also in-keeping with .NET naming conventions, which I'd strongly urge you to follow:
Abc rather than abcdisplay method should be called DisplaySomewhat-conventionally, the class containing the entry point is usually called Program too, but that's less of a strong convention. (It's a better name than Class1 though...)
Most of the time, the compiler doesn't care at all about naming conventions - but in the case of the entry point, the name Main is part of the language specification.
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