This chapter introduced each of the statements of the JavaScript language. Table 6-1 summarizes these statements, listing the syntax and purpose of each.
|
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 [ = value_1] [ ..., name_n [ = value_n]]; |
Declare and initialize variables. |
| while | while (expression) statement |
A basic loop construct. |
| with | with (object) statement |
Extend the scope chain. (Deprecated.) |