Updating array element by reassigning it to different variable?-CodePudding

First of all, sorry if this was asked before, but I simply could not find anything related to it.

string anElement = "World";
string[] col = new string[2] { "Hello", anElement };
anElement = "Jupiter";
Array.ForEach(col, Console.WriteLine);

// Output:
// Hello
// World

As can be seen, reassigning a different value to the anElement reference doesn't update the value.

Same also applies in this scenario:

string[] col = new string[2] { "Hello", "World" };
string elementToUpdate = col[1];
elementToUpdate = "Jupiter";
Array.ForEach(col, Console.WriteLine);

If all the elements are stored as references, why changing col[1]="Jupiter" works while the above does not?

CodePudding user response：

Try this code instead

string anElement = "World";
string[] col = new string[2] { "Hello", anElement };
col[1] = "Jupiter";
Array.ForEach(col, Console.WriteLine);

The problem is you were assigning the value to the anElement, and not getting the item within the array where you needed to make the change

CodePudding user response：

Because local variable string anElement assigned is not used in any execution path. Try this code instead

        string anElement = "World";
        anElement = "Jupiter";
        string[] col = new string[2] { "Hello", anElement };
        Array.ForEach(col, Console.WriteLine);

        // Output:
        // Hello
        // Jupiter