How to break out of 2 loops without a flag variable in C#?

c# syntax

foreach(DataGridViewRow row in grid.Rows)
   foreach(DataGridView cell in row.Cells)
      if (cell.Value == somevalue) {
         // do stuff
         goto End;
      }
End:
   // more stuff

void Loop(grid) {
    foreach(row in grid.Rows)
       foreach(cell in row.Cells)
           if (something) {
               // do stuff   
               return;
           }
}

var cell = (from row in grid.Rows.OfType<DataGridViewRow>()
            from cell in row.Cells.OfType<DataGridViewCell>()
            where cell.Value == somevalue
            select cell
   ).FirstOrDefault();

if (cell != null) {
   // do stuff
}

Though many of the solutions above are correct and answer your question, I would take a step back and ask myself "is there another way to more clearly represent the semantics of the program?"

I would be inclined to write the code like this:

var query = from row in grid.Rows
            from cell in row.Cells
            where cell.Value == myValue
            select cell;
if (query.Any())
{
  // do something useful;
}

Why write any loops at all? You want to know if a particular collection has a particular member, so write a query that asks that question, and then examine the answer.

The most pleasant way is to break the second loop out into a function, like this:

public void DoubleLoop()
{
    for(int i = 0; i < width; i++)
    {
        for(int j = 0; j < height; j++)
        {
            if(whatever[i][j]) break; // let's make this a "double" break
        }
    }
}

goes to

public bool CheckWhatever(int whateverIndex)
{
    for(int j = 0; j < height; j++)
    {
        if(whatever[whateverIndex][j]) return false;
    }

    return true;
}

public void DoubleLoop()
{
    for(int i = 0; i < width; i++)
    {
        if(!CheckWhatever(i)) break;
    }
}

Of course, feel free to simplify this with LINQ or whatever (you could put CheckWhatever into the loop condition, too.) This is just a verbose demonstration of the principle.

I'd just wrap the loops into a function and have the function return as a way to exit the loops for my solution.

        foreach (DataGridViewRow row in grid.Rows)
        {
            foreach (DataGridViewCell cell in row.Cells)
            {
                if (cell.Value == myValue)
                {
                    goto EndOfLoop;
                    //Do Something useful
                    //break out of both foreach loops.
                }
            }

        }
        EndOfLoop: ;

that will work, but I would recommend using a boolean flag.

EDIT: Just to add a little more warning here; it is generally considered bad practice to use goto's as they quickly can lead to spaghetti code that is (nearly) impossible to maintain. That being said, it was included in the C# language, and is available for use, so clearly there are people who believe it has valid usages. Know that the feature exists and use with great caution.

How to break out of 2 loops without a flag variable in C#?

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