Regarding Arrays

Question

Can someone please explain how these are not giving the same results, Thanks

using System;

namespace ArrayandStringPractice
{
class MainClass
{
public static void Main(string[] args)
{

int[] myThirdArray = new int[5] { 1, 5, 3, 6, 8 };

int sum = 0;

for (int j = 0; j < myThirdArray.Length; j++)

{
sum+= j;
Console.WriteLine(sum); //Output is 10
}

int[] myFourthArray = new int[5] { 1, 5, 3, 6, 8 };

int sum1 = 0;

foreach (int j in myFourthArray)
{
sum1 += j;
Console.WriteLine(sum1); //Output is 23
}

}
}
}

Answer 1

for (int j = 0; j < myThirdArray.Length; j++)
{
sum+= j;
Console.WriteLine(sum); //Output is 10
}

Here, j is only the index of array, not the values,

so 0+1+2+3+4 = 10

where,

foreach (int j in myFourthArray)
{
sum1 += j;
Console.WriteLine(sum1); //Output is 23
}

in this case j is actually the numbers inside the array, so
1+5+3+6+8 = 23

Answer 2

aH OK I see. So is this a general rule that the For Loop will deal with the Index and Foeach will deal with the number inside the Array?

I mean how would i make the first part deal with the number inside the array and not the Index?

Answer 3

Brilliant, thanks so much for you help both of you :)