JavaScript for C#Developers Study(1)

JavaScript Basics

• Special number values

Note:

1. 1. 10/0 doesn’t throw exception, it returns NaN instead
   2. NaN doesn’t equal to NaN
   3. use isNaN function to test NaN
   4. isNaN will coalesce string of number

 

• Flow-control statements apply coalescing to boolean

In logical expression, the following values will be treated as false:

1. 1. empty string
   2. number 0
   3. NaN
   4. null
   5. undefined

Otherwise, true

For example, we don’t need to write if(a == null) to test, instead, we simply write if(a)

 

• Reference  Types

• • Object Literals

• • Array Literals

• • Array is an Untyped collection which can hold different type of object inside of it

• Function is a type like Func<> in c#, it can be assigned to a variable.