- JavaScript Basics
- JS Home
- JS Syntax
- JS Placements
- JS Output
- JS Statements
- JS Keywords
- JS Comments
- JS Variables
- JS var
- JS let
- JS const
- JS var Vs let Vs const
- JS Operators
- JS Arithmetic Operators
- JS Assignment Operators
- JS Comparison Operators
- JS Logical Operators
- JS Bitwise Operators
- JS Ternary Operator
- JS Operator Precedence
- JS Data Types
- JS typeof
- JS Conditional Statements
- JS Conditional Statement
- JS if Statement
- JS if...else Statement
- JS switch Statement
- JS Loops
- JS for Loop
- JS while Loop
- JS do...while Loop
- JS break Statement
- JS continue Statement
- JS break Vs. continue
- JavaScript Popup Boxes
- JS Dialog Box
- JS alert Box
- JS confirm Box
- JS prompt Box
- JavaScript Functions
- JS Functions
- JS setTimeout() Method
- JS setInterval() Method
- JavaScript Events
- JS Events
- JS onclick Event
- JS onload Event
- JS Mouse Events
- JS onreset Event
- JS onsubmit Event
- JavaScript Arrays
- JS Array
- JS Find Length of Array
- JS Add Elements at Beginning
- JS Add Element at End
- JS Remove First Element
- JS Remove Last Element
- JS Get First Index
- JS Get Last Index
- JS Reverse an Array
- JS Sort an Array
- JS Concatenate Arrays
- JS join()
- JS toString()
- JS from()
- JS Check if Value Exists
- JS Check if Array
- JS Slice an Array
- JS splice()
- JS find()
- JS findIndex()
- JS entries()
- JS every()
- JS fill()
- JS filter()
- JS forEach()
- JS map()
- JavaScript Strings
- JS String
- JS Length of String
- JS Convert to Lowercase
- JS Convert to Uppercase
- JS String Concatenation
- JS search()
- JS indexOf()
- JS search() Vs. indexOf()
- JS match()
- JS match() Vs. search()
- JS replace()
- JS toString()
- JS String()
- JS includes()
- JS substr()
- JS Slice String
- JS charAt()
- JS repeat()
- JS split()
- JS charCodeAt()
- JS fromCharCode()
- JS startsWith()
- JS endsWith()
- JS trim()
- JS lastIndexOf()
- JavaScript Objects
- JS Objects
- JS Boolean Object
- JavaScript Math/Number
- JS Math Object
- JS Math.abs()
- JS Math.max()
- JS Math.min()
- JS Math.pow()
- JS Math.sqrt()
- JS Math.cbrt()
- JS Math.round()
- JS Math.ceil()
- JS Math.floor()
- JS Math.trunc
- JS toFixed()
- JS toPrecision()
- JS Math.random()
- JS Math.sign()
- JS Number.isInteger()
- JS NaN
- JS Number()
- JS parseInt()
- JS parseFloat()
- JavaScript Date and Time
- JS Date and Time
- JS Date()
- JS getFullYear()
- JS getMonth()
- JS getDate()
- JS getDay()
- JS getHours()
- JS getMinutes()
- JS getSeconds()
- JS getMilliseconds()
- JS getTime()
- JS getUTCFullYear()
- JS getUTCMonth()
- JS getUTCDate()
- JS getUTCDay()
- JS getUTCHours()
- JS getUTCMinutes()
- JS getUTCSeconds()
- JS getUTCMilliseconds()
- JS toDateString()
- JS toLocaleDateString()
- JS toLocaleTimeString()
- JS toLocaleString()
- JS toUTCString()
- JS getTimezoneOffset()
- JS toISOString()
- JavaScript Browser Objects
- JS Browser Objects
- JS Window Object
- JS Navigator Object
- JS History Object
- JS Screen Object
- JS Location Object
- JavaScript Document Object
- JS Document Object Collection
- JS Document Object Properties
- JS Document Object Methods
- JS Document Object with Forms
- JavaScript DOM
- JS DOM
- JS DOM Nodes
- JS DOM Levels
- JS DOM Interfaces
- JavaScript Cookies
- JS Cookies
- JS Create/Delete Cookies
- JavaScript Regular Expression
- JS Regular Expression
- JS RegEx .
- JS RegEx \w and \W
- JS RegEx \d and \D
- JS RegEx \s and \S
- JS RegEx \b and \B
- JS RegEx \0
- JS RegEx \n
- JS RegEx \xxx
- JS RegEx \xdd
- JS RegEx Quantifiers
- JS RegEx test()
- JS RegEx lastIndex
- JS RegEx source
- JavaScript Advance
- JS Page Redirection
- JS Form Validation
- JS Validations
- JS Error Handling
- JS Exception Handling
- JS try-catch throw finally
- JS onerror Event
- JS Multimedia
- JS Animation
- JS Image Map
- JS Debugging
- JS Browser Detection
- JS Security
- JavaScript Misc
- JS innerHTML
- JS getElementById()
- JS getElementsByClassName()
- JS getElementsByName()
- JS getElementsByTagName()
- JS querySelector()
- JS querySelectorAll()
- JS document.write()
- JS console.log()
- JS instanceof
- JavaScript Programs
- JavaScript Programs
JavaScript Debugging
As you know that an error in a program is called as a bug. Therefore, when it is required to debug your JavaScript program then you have to locate and correct the errors of that program.
Basically debugging is a process of finding and rectifying the bugs or defects of a computer program or a piece of electronic hardware.
Debug a JavaScript Program
When you debug a program then first you need to start with a problem, isolate the source of the problem, and finally fix it.
A debugged program means that all the bugs have been removed from the program or you can say that the program is free from errors.
Techniques of Debugging a JavaScript Program
Here are the two techniques you can use to debug your JavaScript program:
- JSLint checker
- Browser sniffing
Debugging JavaScript Program using JSLint Checker
JSLint is an online validator used to debug the JavaScript code. You will find it has two fields, one is text field to set the JavaScript code and second is JSLint button to press and check for errors in your JavaScript code. If your JavaScript code contains any error then JSLint generates the error message with the line number where the error has occurred.
Debugging JavaScript Program using Browser Sniffing
Browser sniffing is a process of detecting the information related to a browser such as name, version, operating system and type of the browser.
Browser sniffing also detects the runtime environment of the browser in which a web page is executed.
Browser sniffing restricts the code fragments of the language that might be JavaScript or any other language that are either having the bugs or not browser specific.
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