JavaScript_syntax

alert(a || b);    // When a is true, there is no reason to evaluate b.
alert(a && b);    // When a is false, there is no reason to evaluate b.
alert(c ? t : f); // When c is true, there is no reason to evaluate f.

alert(a || b); // if a is true, return a, otherwise return b
alert(a && b); // if a is false, return a, otherwise return b

var s = t || "(default)"; // assigns t, or the default value if t is null, empty, etc.  



str = "ab" + "cd";   // "abcd"
str += "e";          // "abcde"
 
str2 = "2"+2         // "22", not "4" or 4.


// SWICH: 

switch (expr) {
   case SOMEVALUE:
     //statements;
     break;
   case ANOTHERVALUE:
     //statements;
     break;
   default:
     //statements;
     break;
 }  




var z;
var  x= z || 1;


switch (x) {  
   case 2:  
    alert("");
     break;  
   case 1:  
    alert(x);

   default:  
     //statements;  
     break;  
 } 



//IN:

 

for (var property_name in some_object) {
   //statements using some_object[property_name];
 } 

var person={fname:"John",lname:"Doe",age:25};

for (x in person)
{
alert(person[x] + " ");
}


//Object literals and array literals allow one to easily create flexible data structures:

var myStructure = {
  name: {
    first: "Mel",
    last: "Smith"
  },
  age: 33,
  hobbies: ["chess", "jogging"]
}; 

 --------------------



var myStructure = {  
  name: {  
    first: "Mel",  
    last: "Smith"  
  },  
  age: 33,  
  hobbies: ["chess", "jogging"]  
};   


for (x in myStructure)
{
alert(myStructure[x] + " ");
}

//Object
//33
//chess,jogging




alert(myStructure.name.first);

//Mel



alert(myStructure.hobbies[0]);
//chess