JavaScript: The Definitive Guide, Fourth Edition

Summary of JavaScript Statements

This chapter introduced each of the statements of the JavaScript language. Table 6-1 summarizes these statements, listing the syntax and purpose of each.

Table 6-1. JavaScript statement syntax

Statement	Syntax	Purpose
break	break; break labelname;	Exit from the innermost loop or switch statement or from the statement named by label.
case	case expression:	Label a statement within a switch statement.
continue	continue; continue labelname;	Restart the innermost loop or the loop named by label.
default	default:	Label the default statement within a switch statement.
do/while	do statement while (expression);	An alternative to the while loop.
empty	;	Do nothing.
for	for (initialize ; test ; increment) statement	An easy-to-use loop.
for/in	for (variable in object) statement	Loop through the properties of an object.
function	function funcname([arg1[..., argn]]) { statements }	Declare a function.
if/else	if (expression) statement1 [else statement2]	Conditionally execute code.
label	identifier: statement	Give statement the name identifier.
return	return [expression];	Return from a function or return the value of expression from a function.
switch	switch (expression) { statements }	Multiway branch to statements labeled with case or default: .
throw	throw expression;	Throw an exception.
try	try { statements } catch (identifier) { statements } finally { statements }	Catch an exception.
var	var name_1 [ ...