with Statement
Establishes the default object for a statement.
with (object)
statement
Arguments
object
Required. The new default object.statement
Required. Statements for which object is the default object. Can be a compound statement.
Remarks
The with statement is commonly used to shorten the amount of code that you have to write in certain situations.
Example
In the example that follows, notice the repeated use of Math.
var x, y;
x = Math.cos(3 * Math.PI) + Math.sin(Math.LN10);
y = Math.tan(14 * Math.E);
When you use the with statement, your code becomes shorter and easier to read:
var x, y;
with (Math){
x = cos(3 * PI) + sin (LN10);
y = tan(14 * E);
}