Regular Expressions 101
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Regular Expressions 101
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JavaScript Validation with regular expression [21 exercises with solution]
[An editor is available at the bottom of the page to write and execute the scripts.]1. Write a JavaScript program to test the first character of a string is uppercase or not.
Go to the editor
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2. Write a JavaScript program to check a credit card number. Go to the editor
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3. Write a pattern that matches e-mail addresses. Go to the editor
The personal information part contains the following ASCII characters.
- Uppercase (A-Z) and lowercase (a-z) English letters.
- Digits (0-9).
- Characters ! # $ % & ' * + - / = ? ^ _ ` { | } ~
- Character . ( period, dot or fullstop) provided that it is not the first or last character and it will not come one after the other.
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4. Write a JavaScript program to search a date within a string. Go to the editor
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5. Write a JavaScript program that work as a trim function (string) using regular expression. Go to the editor
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6. Write a JavaScript program to count number of words in string. Go to the
editor
Note :
- Remove white-space from start and end position.
- Convert 2 or more spaces to 1.
- Exclude newline with a start spacing.
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7. Write a JavaScript function to check whether a given value is IP value or not. Go to the editor
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8. Write a JavaScript function to count the number of vowels in a given string. Go
to the editor
Test Data :
console.log(alphabetize_string('United States'));
Output :
"SUadeeinsttt"
Click me to see the solution
9. Write a JavaScript function to check whether a given value is an valid url or not. Go to the editor
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10. Write a JavaScript function to check whether a given value is alpha numeric or not. Go to the editor
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11. Write a JavaScript function to check whether a given value is time string or not. Go to the editor
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12. Write a JavaScript function to check whether a given value is US zip code or not. Go to the editor
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13. Write a JavaScript function to check whether a given value is UK Post Code or not. Go to the editor
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14. Write a JavaScript function to check whether a given value is Canada Post Code or not. Go to the editor
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15. Write a JavaScript function to check whether a given value is a social security number or not. Go to the editor
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16. Write a JavaScript function to check whether a given value is hexadecimal value or not. Go to the editor
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17. Write a JavaScript function to check whether a given value is hexcolor value or not. Go to the editor
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18. Write a JavaScript function to check whether a given value represents a domain or not. Go to the editor
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19. Write a JavaScript function to check whether a given value is html or not.Go to the editor
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20. Write a JavaScript function to check a given value contains alpha, dash and underscore. Go to the editor
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21. Write a JavaScript function to print an integer with commas as thousands separators. Go to the editor
Test Data :
console.log(thousands_separators(1000));
"1,000"
console.log(thousands_separators(10000.23));
"10,000.23"
console.log(thousands_separators(100000));
"100,000"
Click me to see the solution
More to Come !
* To run the code mouse over on Result panel and click on 'RERUN' button.*
Live Demo:
See the Pen javascript-common-editor by w3resource (@w3resource) on CodePen.
Do not submit any solution of the above exercises at here, if you want to contribute go to the appropriate exercise page.
JavaScript: Tips of the Day
Destructuring
const numbers = [1, 2, 3, 4, 5]; const [y] = numbers; console.log(y);We can unpack values from arrays or properties from objects through destructuring. For example:
The value of a is now 1, and the value of b is now 2. What we actually did in the question, is:
[y] = [1, 2, 3, 4, 5];This means that the value of y is equal to the first value in the array, which is the number 1. When we log y, 1 is returned.
Ref: //bit.ly/323Y0P6