- [Exercises: Date time Object](#exercises-date-time-object)
# 📔Day 1
@ -744,14 +756,17 @@ In JavaScript and other programming language \ followed by some characters is a
* \\': Single quote (')
* \\":Double quote (")
```js
console.log('I hope every one is enjoying the 30 Days Of JavaScript challenge.\nDo you ?') # line break
console.log('I hope every one is enjoying the 30 Days Of JavaScript challenge.\nDo you ?') // line break
console.log('Days\tTopics\tExercises')
console.log('Day 1\t3\t5')
console.log('Day 2\t3\t5')
console.log('Day 3\t3\t5')
console.log('Day 4\t3\t5')
console.log('This is a back slash symbol (\\)') # To write a back slash
console.log('In every programming language it starts with \"Hello, World!\"')
console.log('This is a back slash symbol (\\)') // To write a back slash
console.log('In every programming language it starts with \"Hello, World!\"')
console.log("In every programming language it starts with \'Hello, World!\'")
console.log('The saying \'Seeing is Believing\' is\'t correct in 2020')
```
#### Template Literals(Template Strings)
To create a template string, we use two backticks. We can inject data as expression inside a template string. To inject data, we enclose the expression with a curly bracket({}) followed by a $ sign. See the syntax below.
1. Declare a variable name challenge and assign it to an initial value **'30 Days Of JavaScript'**.
2. Print the string on the browser console using __console.log()__
3. Print the __length__ of the string on the browser console using _console.log()_
4. Change all the string to capital letters using __toUpperCase()__ method
5. Change all the string to lowercase letters using __toLowerCase()__ method
6. Cut(slice) out the first word of the string using __substr()__ or __substring()__ method
7. Slice out the phrase *Days Of JavaScript* from *30 Days Of JavaScript*.
8. Use __substr__ to slice out the phase __because because because__ in the following sentence:__'You cannot end a sentence with because because because is a conjunction'__
9. Check if the string contains a word __Script__ using __includes()__ method
10. Split the __string__ into __array__ using __split()__ method
11. Split the string 30 Days Of JavaScript at the space using __split()__ method
12. 'Facebook, Google, Microsoft, Apple, IBM, Oracle, Amazon' __split__ the string at the comma and change it to an array.
13. Change 30 Days Of JavaScript to 30 Days Of Python using __replace()__ method.
14. What is character at index 15 in '30 Days Of JavaScript' string use __charAt()__ method.
15. What is the character code of J in '30 Days Of JavaScript' string using __charCodeAt()__
16. Use __indexOf__ to determine the position of the first occurrence of a in 30 Days Of JavaScript
17. Use __lastIndexOf__ to determine the position of the last occurrence of a in 30 Days Of JavaScript.
18. Use __indexOf__ to find the position of the first occurrence of the word __because__ in the following sentence:__'You cannot end a sentence with because because because is a conjunction'__
19. Use __lastIndexOf__ to find the position of the first occurrence of the word __because__ in the following sentence:__'You cannot end a sentence with because because because is a conjunction'__
20. Use __search__ to find the position of the first occurrence of the word __because__ in the following sentence:__'You cannot end a sentence with because because because is a conjunction'__
21. Use __trim()__ to remove if there is trailing whitespace at the beginning and the end of a string.E.g ' 30 Days Of JavaScript '.
22. Use __startsWith()__ method with the string *30 Days Of JavaScript* make the result true
23. Use __endsWith()__ method with the string *30 Days Of JavaScript* make the result true
24. Use __match()__ method to find all the a’s in 30 Days Of JavaScript
25. Use __match()__ to count the number all because's in the following sentence:__'You cannot end a sentence with because because because is a conjunction'__
26. Use __concat()__ and merge '30 Days of' and 'JavaScript' to a single string, '30 Days Of JavaScript'
27. Use __repeat()__ method to print 30 Days Of JavaScript 2 times
28. Love is the best thing in this world. Some found their love and some are still looking for their love. Count the number of word love in this sentence.
29. Calculate the total annual income of the person by extract the numbers from the following text. 'He earns 5000 euro from salary per month, 10000 euro annual bonus, 15000 euro online courses per month.'
30. Clean the following text and find the most frequent word(hint, use replace and regular express).
```js
const sentence = '%I $am@% a %tea@cher%, &and& I lo%#ve %tea@ching%;. There $is nothing; &as& mo@re rewarding as educa@ting &and&@emp%o@wering peo@ple. ;I found tea@ching m%o@re interesting tha@n any other %jo@bs. %Do@es thi%s mo@tivate yo@u to be a tea@cher!? %Th#is 30#Days&OfJavaScript &is also $the $result of &love& of tea&ching'
```
31. Using console.log() print out the following statement.
```sh
The quote 'There is no exercise better for the heart than reaching down and lifting people up.' by John Holmes teaches us to help to one another.
```
32. Using console.log() print out the following quote by Mother Teresa.
```sh
"Love is not patronizing and charity isn't about pity, it is about love. Charity and love are the same -- with charity you give love, so don't just give money but reach out your hand instead."
```
# 📔 Day 3
## Booleans
A boolean data type represents one of the two values:_true_ or _false_. Boolean value is either true or false. The use of these data types will be clear when you start the comparison operator. Any comparisons return a boolean value which is either true or false.
@ -1242,42 +1305,82 @@ console.log(count) // -1
### Operator Precendence
I would like to recommend you to read about operator precendence from this [link](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Operator_Precedence)
# 💻 Day 2: Exercises
## Exercises: String Part
## Date Object
Time is an important thing. We like to know the time a certain activity or event. In JavaScript current time and date is created using JavaScript Date Object. The object we create using Date object provides many methods to work with date and time.The methods we use to get date and time information from a date object values are started with a word _get_ because it provide the information.
1. Declare a variable name challenge and assign it to an initial value **'30 Days Of JavaScript'**.
2. Print the string on the browser console using __console.log()__
3. Print the __length__ of the string on the browser console using _console.log()_
4. Change all the string to capital letters using __toUpperCase()__ method
5. Change all the string to lowercase letters using __toLowerCase()__ method
6. Cut(slice) out the first word of the string using __substr()__ or __substring()__ method
7. Slice out the phrase *Days Of JavaScript* from *30 Days Of JavaScript*.
8. Use __substr__ to slice out the phase __because because because__ in the following sentence:__'You cannot end a sentence with because because because is a conjunction'__
9. Check if the string contains a word __Script__ using __includes()__ method
10. Split the __string__ into __array__ using __split()__ method
11. Split the string 30 Days Of JavaScript at the space using __split()__ method
12. 'Facebook, Google, Microsoft, Apple, IBM, Oracle, Amazon' __split__ the string at the comma and change it to an array.
13. Change 30 Days Of JavaScript to 30 Days Of Python using __replace()__ method.
14. What is character at index 15 in '30 Days Of JavaScript' string use __charAt()__ method.
15. What is the character code of J in '30 Days Of JavaScript' string using __charCodeAt()__
16. Use __indexOf__ to determine the position of the first occurrence of a in 30 Days Of JavaScript
17. Use __lastIndexOf__ to determine the position of the last occurrence of a in 30 Days Of JavaScript.
18. Use __indexOf__ to find the position of the first occurrence of the word __because__ in the following sentence:__'You cannot end a sentence with because because because is a conjunction'__
19. Use __lastIndexOf__ to find the position of the first occurrence of the word __because__ in the following sentence:__'You cannot end a sentence with because because because is a conjunction'__
20. Use __search__ to find the position of the first occurrence of the word __because__ in the following sentence:__'You cannot end a sentence with because because because is a conjunction'__
21. Use __trim()__ to remove if there is trailing whitespace at the beginning and the end of a string.E.g ' 30 Days Of JavaScript '.
22. Use __startsWith()__ method with the string *30 Days Of JavaScript* make the result true
23. Use __endsWith()__ method with the string *30 Days Of JavaScript* make the result true
24. Use __match()__ method to find all the a’s in 30 Days Of JavaScript
25. Use __match()__ to count the number all because's in the following sentence:__'You cannot end a sentence with because because because is a conjunction'__
26. Use __concat()__ and merge '30 Days of' and 'JavaScript' to a single string, '30 Days Of JavaScript'
27. Use __repeat()__ method to print 30 Days Of JavaScript 2 times
28. Love is the best thing in this world. Some found their love and some are still looking for their love. Count the number of word love in this sentence.
29. Calculate the total annual income of the person by extract the numbers from the following text. 'He earns 5000 euro from salary per month, 10000 euro annual bonus, 15000 euro online courses per month.'
30. Clean the following text and find the most frequent word(hint, use replace and regular express).
### Creating a time object
Once we create time object. The time object will provide information about time. Let us create a time object
```js
const sentence = '%I $am@% a %tea@cher%, &and& I lo%#ve %tea@ching%;. There $is nothing; &as& mo@re rewarding as educa@ting &and&@emp%o@wering peo@ple. ;I found tea@ching m%o@re interesting tha@n any other %jo@bs. %Do@es thi%s mo@tivate yo@u to be a tea@cher!? %Th#is 30#Days&OfJavaScript &is also $the $result of &love& of tea&ching'
const now = new Date () //
console.log(now) // Sat Jan 04 2020 00:56:41 GMT+0200 (Eastern European Standard Time)
```
We have created a time object and we can access any date time information from the object using the get methods we have mentioned on the table.
### Getting full year
Let's extract or get the full from a time object.
```js
const now = new Date () //
console.log(now.getFullYear()) // 2020
```
### Getting month
Let's extract or get the month from a time object.
```js
const now = new Date () //
console.log(now.getMonth()) // 0, because the month is January, month(0-11)
```
### Getting date
Let's extract or get the date of the month from a time object.
```js
const now = new Date () //
console.log(now.getMonth()) // 0, because the month is January, month(0-11)
```
### Getting hours
Let's extract or get the hours from a time object.
```js
const now = new Date () //
console.log(now.getHours()) // 0, because the time is 00:56:41
```
### Getting minutes
Let's extract or get the minutes from a time object.
```js
const now = new Date () //
console.log(now.getMinutes()) // 56, because the time is 00:56:41
```
### Getting seconds
Let's extract or get the minutes from a time object.
```js
const now = new Date () //
console.log(now.getMinutes()) // 56, because the time is 00:56:41
```
### Getting time
This method give time in milliseconds starting from January 1, 1970. It is also know as Unix time. We can get the unix time in two ways:
1. Using *getTime()*
```js
const now = new Date () //
console.log(now.getTime()) // 1578092201341, this is the number of seconds passed from January 1, 1970 to January 4, 2020 00:56:41
```
2. Using *Date.now()*
```js
const allSeconds = Date.now () //
console.log(allSeconds) // 1578092201341, this is the number of seconds passed from January 1, 1970 to January 4, 2020 00:56:41
const timeInSeconds = new Date ().getTime()
console.log(allSeconds == timeInSeconds) // true
```
Let us format these values to a human readable time format.
Asabeneh
5 years ago
