How to know that an object contains in a list ignoring case

Question

I want to know how to compare an object, that if a list contains that object by ignoring case Suppose take an example for this

Class A
{
    public string p1;
    public string p2;
}

Class B
{
    List<A> lst=new List<A>();
    A obj=new a();
    A obj1=new a();

    obj1.p1="ABCD";
    obj1.p2="xyz";

    obj.p1="abcd";
    obj.p2="XYZ";
    lst.add(obj1);

    lst.contains(obj)//return false
}

So I want to know how to compare it?

Answer 1

You can implement IEquatable to control how your objects are compared. You can then specify exactly how you want the comparison to work by implementing the Equals() method:

 public bool Equals(A other)
 {
     return this.P1.ToLower().Equals(other.P1.ToLower());
 }

Your

lst.Contains(obj)

Should then work as you need.

Answer 2

In class A override the Equals method to compare each of the properties ignoring case.

Then use:

bool found = lst.FirstOrDefault(x => x.Equals(obj)) != null;

Answer 3

var result = lst.FirstOrDefault(c => c.p1 == obj.p1 && c.p2 == obj.p2);
if(result != null)
{
    //Your Code is here.
}