How can a case in a switch not have a break?

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Switch statement fallthrough in C#? 14 answers

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This structure:

case "LogOnManager":
case "NormalUse":
    lblSwipeStatus.Text = "Pass ID BadgenNear The Reader";
    break;

basically means that the code in the second case will be used for either case . So both of the cases use the same code.

Semantically this could be thought of as:

case "LogOnManager" || "NormalUse":
    lblSwipeStatus.Text = "Pass ID BadgenNear The Reader";
    break;

Except that this doesn't compile as a valid condition for that switch statement. (Potentially for a couple of reasons if you want to get really technical, but primarily because this evaluates to a bool and the switch is operating on a string .) So the version you've found does the job instead.

When a break statement is omitted (or, more specifically, when a case block is empty), the process will continue to whatever the next case is, regardless of the value used for that next case .

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If a switch case doesn't have a break, then it will fall through the next case. Note that in C#, it only works if there is nothing in the case body.

From the Documentation:

C# does not support an implicit fall through from one case label to another. The one exception is if a case statement has no code.

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A case without a break in this case just means that it will do the same as the case underneath it.

So either of these cases will do the same thing:

  case "LogOnManager":
  case "NormalUse":
                    lblSwipeStatus.Text = "Pass ID BadgenNear The Reader";
                    break;

It's called fall through

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