Why does Property Set throw StackOverflow exception?

Question

I know java and would normally put in getter/setter methods. I am interested in doing it in C# with the following code, but it throws a StackOverflow exception. What am I doing wrong?

Calling Code

c.firstName = "a";

Property Code

public String firstName;
{
    get
    {
        return firstName;
    }
    set
    {
        firstName = value;
    }
}

Answer 1

It's because you're recursively calling the property - in the set you are setting the property again, which continues ad infinitum until you blow the stack.

You need a private backing field to hold the value, e.g.

private string firstName;  public string FirstName {     get     {         return this.firstName;     }     set     {         this.firstName = value;     } } 

Alternatively, if you're using C# 3.0, you could use an auto-property, which creates a hidden backing field for you, e.g.

public string FirstName { get; set; } 

Answer 2

You are setting the property name inside your property--not the field name. This would work better:

private string m_firstName;  public String firstName; {     get     {         return m_firstName;     }     set     {         m_firstName = value;     } }