basis of javascript

Javascript and Java are alike each other, including control statements and String object.

All control statements such as  if, for, while, swith in java also emerge in javascript . 

 

Code Example:

 var lines = new Array("hello", "world"); for(var i = 0; i < lines.length; i++){ document.write(lines[i] + "<br/>"); } equals to: for( line in lines){ docment.write(line + "<br/>"); }

 

 

 Javascript is a weaky typed language that implies variables maybe equal even their types are not same.
code  example:

1. var s="the " + 1 + "st". int variable is converted into string automaticly. 2. weaky typed equals '==' function fun(){ if("3.0"==3){ document.write("string 3.0 equals int 3:" + true); // string variable can concatenate boolean variable. }else{ document.write(false); } };

 

type convention
  parseInt/parseFloat.

constant
  const PI=3.14