Difference between revisions of "Switch"

Revision as of 05:29, 9 June 2013

Syntax

• switch(<expression>);

Description

The switch statement is similar to a series of if statements on the same expression. In many occasions, you may want to compare the same variable (or expression) with many different values, and execute a different piece of code depending on which value it equals to. This is exactly what the switch statement is for.

It is important to understand how the switch statement is executed in order to avoid mistakes. The switch statement executes line by line (actually, statement by statement). In the beginning, no code is executed. Only when a case statement is found with a value that matches the value of the switch expression the case statement(s) will to executed. The parser continues to execute the statements until the end of the switch block, or the first time it sees a break statement. If you don't write a break statement at the end of a case's statement list, the parser will go on executing the statements of the following case (fall-through).

Example

// Returns the number of refines on your top headgear
set(.@refCount, getequiprefinerycnt(EQI_HEAD_TOP));
// Output a message
switch(.@refCount) {
	// 0 means no refine yet
	case 0:
		mes("No refine on your top headgear yet?");
		mes("You need to go to the refiner!");
		break;

	// +1
	case 1:
		mes("Your top headgear is +1!");
		break;
	// +2
	case 2:
		mes("Your top headgear is +2!");
		break;

	// +3
	case 3:
		mes("Your top headgear is +3!");
		break;

	// +4
	case 4:
		mes("Your top headgear is +4!");
		// NOTE: no break here means the code from "case 5" will be executed afterwards!
	
	// +5
	case 5:
		mes("Your top headgear is +5!");
		break;

	// [...]

	// This case will be triggered if no other case was triggered yet
	default:
		mes("Your top headgear has upgrades above +5!");
		break;
}

Next Example

switch(rand(1,3)) {
	case 1:
 		mes "Randomly Selected Number is 1";
 		break;
	case 2:
 		mes "Randomly Selected Number is 2";
 		break;
	case 3:
 		mes "Randomly Selected Number is 3";
 		break;
 }