Question

I have two List<int> instances. Now I want to combine them into a third list.

public List<int> oldItemarry1 // storing old item
{
    get 
    { 
        return (List<int>)ViewState["oldItemarry1 "]; 
    }
    set 
    { 
        ViewState["oldItemarry1 "] = value; 
    }
}

public List<int> newItemarry1 // storing new item
{
    get
    { 
        return (List<int>)ViewState["newItemarry1 "]; 
    }
    set 
    { 
        ViewState["newItemarry1 "] = value; 
    }
}

public List<int> Itemarry1 // want to combine both the item
{
    get
    { 
        return (List<int>)ViewState["Itemarry1 "]; 
    }
    set 
    { 
        ViewState["Itemarry1 "] = value; 
    }
}

Please some one tell me how to do that?

Answer 1

Use the Union method; it will exclude duplicates.

int[] combinedWithoutDups = oldItemarry1.Union(newItemarry1).ToArray();