JavaScript syntax
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Control structures
Compound statements
A pair of curly brackets { } and an enclosed sequence of statements constitute a compound statement, which can be used wherever a statement can be used.
If ... else
if (expr) {
//statements;
} else if (expr2) {
//statements;
} else {
//statements;
}
Conditional (ternary) operator
The conditional operator creates an expression that evaluates as one of two expressions depending on a condition. This is similar to the if statement that selects one of two statements to execute depending on a condition. I.e., the conditional operator is to expressions what if is to statements.
const result = condition ? expression : alternative;
is the same as:
if (condition) {
const result = expression;
} else {
const result = alternative;
}
Unlike the if statement, the conditional operator cannot omit its "else-branch".
Switch statement
The syntax of the JavaScript switch statement is as follows:
switch (expr) {
case SOMEVALUE:
// statements;
break;
case ANOTHERVALUE:
// statements for when ANOTHERVALUE || ORNAOTHERONE
// no break statement, falling through to the following case
case ORANOTHERONE:
// statements specific to ORANOTHERONE (i.e. !ANOTHERVALUE && ORANOTHER);
break; //The buck stops here.
case YETANOTHER:
// statements;
break;
default:
// statements;
break;
}
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