JavaScript For...In Statement

The for...in statement loops through the properties of an object.

Syntax
Code:
for (variable in object)
  {
      code to be executed
  }
Note: The code in the body of the for...in loop is executed once for each property.

Example
Looping through the properties of an object:
Code:
var person={fname:"John",lname:"Doe",age:25}; 

for (x in person)
{
document.write(person[x] + " ");
}
Try it yourself »