C＃相当于Java的继续<label>？

Question

Should be simple and quick: I want a C# equivalent to the following Java code:

orig: for(String a : foo) {
  for (String b : bar) {
    if (b.equals("buzz")) {
      continue orig;
    }
  }
  // other code comes here...
}

---

Edit : OK it seems there is no such equivalent (hey - Jon Skeet himself said there isn't, that settles it ;)). So the "solution" for me (in its Java equivalent) is:

for(String a : foo) {
  bool foundBuzz = false;
  for (String b : bar) {
    if (b.equals("buzz")) {
      foundBuzz = true;
      break;
    }
  }
  if (foundBuzz) {
    continue;
  }
  // other code comes here...
}

Answer 1

I don't believe there's an equivalent, I'm afraid. You'll have to either use a boolean, or just "goto" the end of the inside of the outer loop. It's even messier than it sounds, as a label has to be applied to a statement - but we don't want to do anything here. However, I think this does what you want it to:

using System;

public class Test
{
    static void Main()
    {
        for (int i=0; i < 5; i++)
        {
            for (int j = 0; j < 5; j++)
            {
               Console.WriteLine("i={0} j={1}", i, j);
               if (j == i + 2)
               {
                   goto end_of_loop;   
               }
            }
            Console.WriteLine("After inner loop");
            end_of_loop: {}
        }
    }
}

I would strongly recommend a different way of expressing this, however. I can't think that there are many times where there isn't a more readable way of coding it.

Answer 2

Other posibility is to make a function with the inner loop:

void mainFunc(string[] foo, string[] bar)
{
  foreach (string a in foo)
    if (hasBuzz(bar))
      continue;
  // other code comes here...
}

bool hasBuzz(string[] bar)
{
  foreach (string b in bar)
    if (b.equals("buzz"))
      return true;
  return false;
}

Answer 3

In VB.Net, you could just have one while loop and one for loop and then exit the desired scope level.

In C#, maybe break; ?

That might break out of the inner loop and allow the outer loop to keep going.

Answer 4

I think you're looking for the simple "continue" keyword... However, not being a Java guy I don't really get what the code snippet is trying to achieve.

Consider the following, though.

foreach(int i in new int[] {1,2,3,5,6,7})
{
    if(i % 2 == 0)
        continue;
    else
        Console.WriteLine(i.ToString());    
}

The continue statement on line 4 is an instruction to continue with the loop at the next value. The output here would be 1,3,5 and 7.

Replacing "continue" with "break", as follows,

foreach(int i in new int[] {1,2,3,5,6,7})
{
    if(i % 2 == 0)
       break;
    else
        Console.WriteLine(i.ToString());    
}

will give the output 1. Break instructs the loop to terminate, most commonly used when you want to stop processing when a condition is met.

I hope this gives you some of what you were looking for, but if not, feel free to ask again.

Answer 5

You could do something like:

for(int i=0; i< foo.Length -1 ; i++) {
  for (int j=0; j< bar.Length -1; j++) {
    if (condition) {
      break;
    }
    if(j != bar.Length -1)
        continue;
    /*The rest of the code that will not run if the previous loop doesn't go all the way*/
  }
}