diff --git a/README.md b/README.md index 9ea5671..d111976 100644 --- a/README.md +++ b/README.md @@ -18,15 +18,13 @@ function sum(x, y) { }; } } -``` - -Output -```js console.log(sum(2,3)); // Outputs 5 console.log(sum(2)(3)); // Outputs 5 ``` +**⚝ [Try this example on CodeSandbox](https://codesandbox.io/s/js-cp-1-ypmjhl?file=/src/index.js)** +
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@@ -36,69 +34,41 @@ console.log(sum(2)(3)); // Outputs 5 ```html - - - Show File Data - - - -
- - -
- + console.log("File Name: " + file.name); + console.log("File Size: " + file.size + " bytes"); + console.log("File Extension: " + extension); + } + + + + +
+ + +
+ + + + +File Name: pic.jpg +File Size: 1159168 bytes +File Extension: jpg ``` +**⚝ [Try this example on CodeSandbox](https://codesandbox.io/s/js-cp-file-upload-fj17kh?file=/index.html)** +
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@@ -115,34 +85,20 @@ console.log(sum(2)(3)); // Outputs 5 var captcha; function generateCaptcha() { - var a = Math.floor(Math.random() * 10); - var b = Math.floor(Math.random() * 10); - var c = Math.floor(Math.random() * 10); - var d = Math.floor(Math.random() * 10); - - captcha = a.toString() + b.toString() + c.toString() + d.toString(); + captcha = Math.floor(Math.random() * 1000000); document.getElementById("captcha").value = captcha; } - - function check() { - var input = document.getElementById("inputText").value; - - if (input == captcha) { - alert("Valid Captcha"); - } else { - alert("Invalid Captcha"); - } - } +

-

- ``` +**⚝ [Try this example on CodeSandbox](https://codesandbox.io/s/js-cp-captcha-mzyi2n?file=/index.html)** +
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@@ -155,107 +111,74 @@ console.log(sum(2)(3)); // Outputs 5 Stopwatch Example + -
-

Simple stopwatch made in JavaScript

- - - -
-

- 0 : 00 : - 000 -

-

- In this example Date() methods co-operate with timing function - setInterval(). -

+

Time: 00:00:00



+ + + ``` +**⚝ [Try this example on CodeSandbox](https://codesandbox.io/s/js-cp-stopwatch-j6in1i?file=/index.html)** +
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@@ -270,9 +193,13 @@ function reverseString(str) { } return stringRev; } -alert(reverseString("Pradeep")); // Output: peedarP +console.log(reverseString("Hello")); + +// Output: olleH ``` +**⚝ [Try this example on CodeSandbox](https://codesandbox.io/s/js-cp-reversestring-sgm1ip?file=/src/index.js)** +
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@@ -283,19 +210,39 @@ alert(reverseString("Pradeep")); // Output: peedarP function isEmpty(obj) { return Object.keys(obj).length === 0; } + +const obj = {}; +console.log(isEmpty(obj)); // true ``` +**⚝ [Try this example on CodeSandbox](https://codesandbox.io/s/js-cp-isempty-b7n04b?file=/src/index.js)** + +
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+ ## Q. ***JavaScript Regular Expression to validate Email*** ```javascript -var pattern = /^\w+@[a-zA-Z_]+?\.[a-zA-Z]{2,3}$/; +function validateEmail(email) { + const re = /\S+@\S+\.\S+/; + return re.test(email); +} + +console.log(validateEmail("pradeep.vwa@gmail.com")); // true ``` +**⚝ [Try this example on CodeSandbox](https://codesandbox.io/s/js-cp-validateemail-wfopym?file=/src/index.js)** + +
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+ ## Q. ***Use RegEx to test password strength in JavaScript?*** ```javascript -var newPassword = "Pq5*@a{J"; -var regularExpression = new RegExp( +let newPassword = "Pq5*@a{J"; +const regularExpression = new RegExp( "^(?=.*[a-z])(?=.*[A-Z])(?=.*[0-9])(?=.*[!@#$%^&*])(?=.{8,})" ); @@ -303,7 +250,12 @@ if (!regularExpression.test(newPassword)) { alert( "Password should contain atleast one number and one special character !" ); +} else { + console.log("PASS"); } + +// Output +PASS ``` | RegEx | Description | @@ -315,6 +267,8 @@ if (!regularExpression.test(newPassword)) { | (?=.[!@#\$%\^&]) | The string must contain at least one special character, but we are escaping reserved RegEx characters to avoid conflict | | (?=.{8,}) | The string must be eight characters or longer | +**⚝ [Try this example on CodeSandbox](https://codesandbox.io/s/js-cp-password-strength-cxl8xy)** +
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@@ -8066,23 +8020,135 @@ c.retrieve(); // => The counter is currently at: 14 ## Q. ***How to divide an array in multiple equal parts in JS?*** ```js -function splitArrayIntoChunksOfLen(arr, len) { - let chunks = [], - i = 0, - n = arr.length; +const arr = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]; +let lenth = 3; - while (i < n) { - chunks.push(arr.slice(i, (i += len))); +function split(len) { + while (arr.length > 0) { + console.log(arr.splice(0, len)); } - return chunks; } -let alphabet = ["a", "b", "c", "d", "e", "f"]; -let alphabetPairs = splitArrayIntoChunksOfLen(alphabet, 2); //split into chunks of two +split(lenth); + +// Output +(3) [1, 2, 3] +(3) [4, 5, 6] +(3) [7, 8, 9] +(1) [10] +``` + +**⚝ [Try this example on CodeSandbox](https://codesandbox.io/s/split-array-5od3rz)** + +
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+ +## Q. ***Write a random integers function to print integers with in a range?*** + +**Example:** + +```js +/** + * function to return a random number + * between min and max range + * + * */ +function randomInteger(min, max) { + return Math.floor(Math.random() * (max - min + 1) ) + min; +} +randomInteger(1, 100); // returns a random integer from 1 to 100 +``` + +**⚝ [Try this example on CodeSandbox](https://codesandbox.io/s/js-random-integers-yd1cy8?file=/src/index.js)** + +
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+ +## Q. ***How to convert Decimal to Binary in JavaScript?*** + +**Example 01:** Convert Decimal to Binary + +```js +function DecimalToBinary(number) { + let bin = 0; + let rem, + i = 1; + while (number !== 0) { + rem = number % 2; + number = parseInt(number / 2); + bin = bin + rem * i; + i = i * 10; + } + console.log(`Binary: ${bin}`); +} + +DecimalToBinary(10); +``` + +**Example 02:** Convert Decimal to Binary Using `toString()` + +```js +let val = 10; + +console.log(val.toString(2)); // 1010 ==> Binary Conversion +console.log(val.toString(8)); // 12 ==> Octal Conversion +console.log(val.toString(16)); // A ==> Hexadecimal Conversion +``` + +**⚝ [Try this example on CodeSandbox](https://codesandbox.io/s/js-decimal-to-binary-uhyi8t?file=/src/index.js)** + +
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+ +## Q. ***How do you make first letter of the string in an uppercase?*** + +You can create a function which uses chain of string methods such as charAt, toUpperCase and slice methods to generate a string with first letter in uppercase. + +```js +function capitalizeFirstLetter(string) { + let arr = string.split(" "); + for (var i = 0; i < arr.length; i++) { + arr[i] = arr[i].charAt(0).toUpperCase() + arr[i].slice(1); + } + return arr.join(" "); +} + +console.log(capitalizeFirstLetter("hello world")); // Hello World +``` + +**⚝ [Try this example on CodeSandbox](https://codesandbox.io/s/js-capitalizefirstletter-dpjhky?file=/src/index.js)** + +
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+ +## Q. ***Write a function which will test string as a literal and as an object?*** + +The `typeof` operator can be use to test string literal and `instanceof` operator to test String object. + +```js +function check(str) { + if (str instanceof String) { + return "It is an object of string"; + } else { + if (typeof str === "string") { + return "It is a string literal"; + } else { + return "another type"; + } + } +} + +var ltrlStr = "Hi I am string literal"; +var objStr = new String("Hi I am string object"); -console.log(alphabetPairs); +console.log(check(ltrlStr)); // It is a string literal +console.log(check(objStr)); // It is an object of string ``` -**⚝ [Try this example on CodeSandbox](https://codesandbox.io/s/splitarrayintochunksoflen-5od3rz?file=/src/index.js:0-345)** +**⚝ [Try this example on CodeSandbox](https://codesandbox.io/s/js-literal-vs-object-978dqw?file=/src/index.js)**
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