How does List.IndexOf() perform comparisons on custom objects?

Question

I wrote a class of account objects and hold a static List of those account objects. My program loops through each account in the list, performing some

Answer 1

Your object should implement the IEquatable interface and override the Equals method.

public class Account : IEquatable
{
    public string name;
    public string password;
    public string newInfo;

    public bool Equals(Account other)
    {
       //Choose what you want to consider as "equal" between Account objects  
       //for example, assuming newInfo is what you want to consider a match
       //(regardless of case)
       if (other == null) 
             return false;

       return String.Equals(this.newInfo, other.newInfo, 
                           StringComparison.OrdinalIgnoreCase);
    }
}