JavaScript Cheet Sheet

Example 1

// Demonstrates two ways to declare a string
var firstString = new String("I'm a String!");
var secondString = "I'm another String!";
example1a.innerText = firstString;
example1b.innerText = secondString;

Example 1 Output

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Example 2

// Demonstrates two ways to declare a string
var aString = "I'm another String!";
example2a.innerText = aString;
example2b.innerText = "aString length is: "+aString.length;

Example 2 Output

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Example 3

// Demonstrates indexOf Method
var aString = "Hello, my name is Daniel Striukas. What's your name?";
example3a.innerText = aString;
example3b.innerText = "First instance \"name\" starts at index: " +aString.indexOf("name");

Example 3 Output

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Example 4

// Demonstrates lastIndexOf Method
var aString = "Hello, my name is Daniel Striukas. What's your name?";
example3a.innerText = aString;
example3b.innerText = "Last instance \"name\" starts at index: " +aString.lastIndexOf("name");

Example 4 Output

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Example 5

// Demonstrates substring Method
var aString = "Hello, my name is Daniel Striukas. What's your name?";
var newString = aString.substring(18,26);
// Parameters 18 and 26 copies the respective indexes from aString to newString
example5a.innerText = newString;

Example 5 Output

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Example 6

// Demonstrates substr Method
var aString = "Hello, my name is Daniel Striukas. What's your name?";
var newString = aString.substr(18,26);
// Parameters 18 and 26 cut the respective indexes from aString
// Unlike the substring Method, the second parameter starting point is from at index 18, so in relation to aString varaible, substr cuts from index 18 to index 36 (18+26)
example6a.innerText = newString;

Example 6 Output

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Example 7

// Demonstrates toUpperCase & toLowerCase Methods
var aString = "Hello, my name is Daniel Striukas. What's your name?";
example7a.innerText = aString.toUpperCase();
example7b.innerText = aString.toLowerCase();

Example 7 Output

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Example 8

// Demonstrates charAt() & charCodeAt() Methods
var aString = "I love JavaScript!";
example8a.innerText = "Character at index 7 is: " +aString.charAt(7);
example8b.innerText = "The code for this character is: " +aString.charCodeAt(7);

Example 8 Output

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Example 9

// Demonstrates fromCharCode() Method
// This is a static method, so you use String.fromCharCode()
var someCharacters = String.fromCharCode(74,75,76);
// The parameters are numbers which represent the decimal unicode for characters.
example9a.innerText = someCharacters;

Example 9 Output

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