How do I jump out of a foreach loop in C#?

Use break; and this will exit the foreach loop

foreach (string s in sList)
{
    if (s.equals("ok"))
        return true;
}

return false;

Alternatively, if you need to do some other things after you've found the item:

bool found = false;
foreach (string s in sList)
{
    if (s.equals("ok"))
    {
        found = true;
        break; // get out of the loop
    }
}

// do stuff

return found;