Table of contents
- 1. Summary
- 2. Syntax
- 3. Parameters
- 4. Description
- 5. Examples
- 6. See also
Summary
Iterates a specified variable over all values of object's properties. For each distinct property, a specified statement is executed.
| Statement | |
| Implemented in: | JavaScript 1.6 |
| ECMA Version: | none |
Syntax
for each (variable in object) statement
Parameters
-
variable - Variable to iterate over property values, optionally declared with the
varkeyword. This variable is local to the function, not to the loop.
-
object - Object for which the properties are iterated.
-
statement - A statement to execute for each property. To execute multiple statements within the loop, use a block statement (
{ ... }) to group those statements.
Description
Some built-in properties are not iterated over. These include all built-in methods of objects, e.g. String's indexOf method. However, all user-defined properties are iterated over.
Examples
Example: Using for each...in
Warning: Never use a loop like this on arrays. Only use it on objects. Details.
The following snippet iterates over an object's properties, calculating their sum:
var sum = 0;
var obj = {prop1: 5, prop2: 13, prop3: 8};
for each (var item in obj) {
sum += item;
}
print(sum); // prints "26", which is 5+13+8
See also
- for...in - a similar statement that iterates over the property names.
- for
- Array comprehensions (these use
for each)
