Javascript Values part 1
Primitive Data Types
Immutables (not chageables)
// Primitive Data Types
String // 'Javascript is awesome!', "Really awesome!"
Number // 4, 150, 2345, 4.5
Boolean // true, false, -1, 0, 1,
null // "defined" as no value
undefined // not yet defined
Strings
Data type for plain language
Strings
// Javascript Strings
// Must be between balanced quotes
typeof 'Javascript is awesome!'; // 'string'
// Escape special characters
'Can\'t beat Javascript so don\'t try';
// Can contain numbers and symbols
'Jenny: ($#@)867-5309';
Strings
// Javascript Strings
// Indexed, starting at 0
'string'[0]; // 's'
// Iterable (can loop through)
for (var index = 0; index < 9; index++) {
console.log('JScript'[index]);
}
// 'J', 'S', 'c', 'r', 'i', 'p', 't'
// Immutable
'I hear the secrets that...'[2] = 'f'; // NOPE!!! String Methods (helpers)
// String Methods (helpers)
// How many characters?
'Don\'t sweat the technique'.length // 24
// Convert to uppercase
'dance, magic dance!'.toUpperCase // 'DANCE, MAGIC DANCE'
// Where is the letter
'Borderline!'.indexOf('r'); // 2
// Search for other Javascript string methods
// Use them when possibleStrings
- Primitive Javascript Data Type
- Immutable (no editing)
- Characters, symbols, numbers
- Escape special characters
- Must be between balanced quotes
Key Takeaways
Strings
Let's code!!!
[Add link to exercises here and/if directions]
[Anything else?]:
new pairs?
how long?
Resources?
Numbers
Just do all the stuff you do with numbers...
Numbers
// Javascript Numbers
// Numbers are numbers
13, 2357, 5634634564356456
// Decimals too
45.33466362363JavaScript Memory
563463456...
2357
45.3346636...
13
Numbers
// Javascript Numbers
// Mathmatical operations
> 21 + 7: // 28
> 3.14 + 5: // 8.4
> 3 * 5; // 15
> 15 / 3 // 5
> 15 % 9; // 6
JavaScript Memory
3 * 5
3.14 + 5
15 / 3
21 + 7
15 % 9
Numbers
// Javascript Numbers
// Mathmatical operations
> 21 + 7: // 28
> 3.14 + 5: // 8.4
> 3 * 5; // 15
> 15 / 3 // 5
> 15 % 9; // 6
JavaScript Memory
15
8.4
5
28
6
Numbers
// Javascript Numbers Methods
// Is this a number?
typeof 523454 // ???
// 'STRINGIFY' this number
55.00.toString(); // ???
77.toString(); // ???
(99).toString(); // ???
// Numberify a 'STRINGIFIED'
Number('453'); // ???JavaScript Memory
ERROR
55
"99"
"number"
453
Numbers Methods (helpers)
// Javascript Numbers Methods
// Is this a number?
typeof 523454 // ???
// 'STRINGIFY' this number
55.00.toString(); // ???
77.toString(); // ???
(99).toString(); // ???
// Numberify a 'STRINGIFIED'
Number('453'); // ???Numbers Methods (helpers)
// Javascript Numbers Methods
// When adding numbers
600 + '400'; // ???
// When using some methods
54.435345.toFixed(2); // ???
// Combining methods and operations
10 + 54.435345.toFixed(2); // ???
Be Careful and pay attention to detail!
Numbers Methods (helpers)
// Javascript Numbers Methods
// When adding numbers
600 + '400'; // '600400'
// When using some methods
54.435345.toFixed(2); // '54.44'
// Combining methods and operations
10 + 54.435.toFixed(2); // '1054.44'
// Just to be safe???
Number(10 + 54.435.toFixed(2)); // ???
Be Careful and pay attention to detail!
Numbers Methods (helpers)
// Javascript Numbers Methods
// What's this???
Number(10 + 54.435.toFixed(2)); // ???
Be Careful and pay attention to detail!
// And what about this?
Number(54.435.toFixed(2) + 10); // ???// And this?
Number(54.435345.toFixed(2)) + 10; // ???Numbers Methods (helpers)
// Javascript Numbers Methods
// What's this???
Number(10 + 54.435.toFixed(2)); // 1054.44
Be Careful and pay attention to detail!
// And what about this?
Number(54.435.toFixed(2) + 10); // 54.441// And this?
Number(54.435345.toFixed(2)) + 10; // 64.44Numbers
- Primitive Javascript Data Type
- Immutable (no editing)
- Do number stuff
- Be careful when using methods
- Be when using with strings
Key Takeaways
Numbers
Let's code!!!
[Add link to exercises here and/if directions]
[Anything else?]:
new pairs?
how long?
Resources?
Ver 1.0
By telegraphprep
