10 Adet Javascript Kestirmesi

1. Ondalık sayılar

/* Shorthand */
var myVar = 1e8;
 
/* Longhand */
var myVar = 100000000;

2. Artış, azalma

/* Shorthand */
i++;
j--;
 
/* Longhand */
i=i+1;
j=j-1;

3. Ekle, çıkar, çarp, böl

/* Shorthand */
i+=5;
j-=3;
k*=10;
l/=2;
 
/* Longhand */
i=i+5;
j=j-3;
k=k*10;
l=l/2;

4. Karakter pozisyonunu belirleyin

var myString = "Happy birthday";
 
/* Shorthand */
myString[4];
 
/* Longhand */
myString.charAt(4);

5. Değişkenleri toplu olarak bildirin

/* Shorthand */
var i, j=5, k="Good morning", l, m=false;
 
/* Longhand */
var i;
var j=5;
var k="Good morning";
var l;
var m=false;

6. İlişkisel bir dizi bildirin

/* Shorthand */
var myArray  = {
  "Grace Kelly": "Philadelphia",
  "Clint Eastwood": "San Francisco",
  "Humphrey Bogart": "New York City",
  "Sophia Loren": "Rome",
  "Ingrid Bergman": "Stockholm"
}
 
/* Longhand */
var myArray = new Array();
myArray["Grace Kelly"] = "Philadelphia";
myArray["Clint Eastwood"] = "San Francisco";
myArray["Humphrey Bogart"] = "New York City";
myArray["Sophia Loren"] = "Rome";
myArray["Ingrid Bergman"] = "Stockholm";

7. Nesneyi bildirin

/* Shorthand */
var myObj = { name: "Sean Connery", placeOfBirth: "Edinburgh",
age: 86, wasJamesBond: true };
 
/* Longhand */
var myObj = new Object();
myObj.name = "Sean Connery";
myObj.placeOfBirth = "Edinburgh";
myObj.age = 86;
myObj.wasJamesBond = true;

8. Koşullu operatörü kullanın

var age = 17;
 
/* Shorthand */
var message = age >= 18 ? "Allowed" : "Denied";
 
/* Longhand */
if( age >= 18) {
  var message = "Allowed";
} else {
  var message = "Denied";
}

9. Varlığı kontrol etme

var myVar = 99;
 
/* Shorthand */
if( myVar ) {
  console.log("The myVar variable is defined AND it's not empty
  AND not null AND not false.");
}
 
/* Longhand */
if( typeof myVar !== "undefined" && myVar !==  "" && myVar !== null
&& myVar !== 0 && myVar !== false  ) {
  console.log("The myVar variable is defined AND it's not empty
  AND not null AND not false.");

10. Yokluğunu kontrol etme

var myVar;
 
/* Shorthand */
if( !myVar ) {
  console.warn("The myVar variable is undefined (OR) empty (OR)
  null (OR) false.");
}
 
/* Longhand */
if( typeof myVar === "undefined" || myVar === "" || myVar === null
|| myVar === 0 || myVar === false  ) {
  console.warn("The myVar variable is undefined (OR) empty (OR)
  null (OR) false.");
}