using System.Collections;
using System.Collections.Generic;
 
public class Program {
	public static void Main() {
		var array = new ArrayList() { 1, "texto" };
		var total = 0;
		foreach (var item in array) {
		    //total += item; //se tirar o comentário dá erro quando tentar somar a string
		}
		//array[1].Contains("t"); //mesmo sendo string não pode acessar Contains() porque o tipo é object
		((string)array[1]).Contains("t");
		var list = new List<int>() { 1, /*"texto"); //<-- Error at compile process //ddaria erro aqui*/ };
		total = 0;
		foreach (var item in list) total += item;
	}
}
 
//https://pt.stackoverflow.com/q/227678/101

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