List of JavaScript functions

In this tutorial, we are going to see the list of the native functions most used in Javascript.
 

Array Methods

• pop(): Remove the last element from an array
• push(): Add a new element at the end of the array
• sort(): Sort the elements in alphabetical order
• reverse(): Sort the elements in descending order
• shift(): Remove the first element from an array
• toString(): Convert elements to strings
• unshift(): Add a new element at the start of an array
• concat(): Merge several arrays into one
• join(): Combines the elements of an array into a single string and returns the string
• slice(): Copy part of an array to a new array
• splice(): Is used to modify the contents of an array by removing existing elements and / or adding new elements.
• valueOf(): Returns the primitive value of the specified object
• indexOf(): Returns the first index at which the given element can be found in an array, or -1 if it is not present in an array.
• lastIndexOf(): Returns the last index at which the given element can be found in an array, or -1 if it is not present in an array.

 

Methods for displaying the output data

• alert(): Show output to a browser dialog box
• confirm(): Opens a yes/no dialog and returns true/false depending on the user’s click
• console.log(): Displays the output to the browser console, useful for debugging
• document.write(): Writes directly to the HTML document

 

Global functions

• isNaN(): Determines if a value is NaN (Not a Number) or not
• Number(): Converts the argument to a number representing the value of the object. If the value cannot be converted to a number, NaN is returned.
• eval(): Evaluates the JavaScript code represented as a string
• encodeURI(): Encode a URI in UTF-8
• decodeURI(): Decode a URI created by encodeURI () or other functions
• decodeURIComponent(): Decode a URI component
• parseInt(): convert a character string into an integer
• parseFloat(): convert a string to a floating point number
• isFinite(): Determines if the transmitted value is a finite number

 

Methods of the String object

• match(): Retrieves the matches of a string based on a search pattern
• search(): Searches a string for the specified value and returns the position of the match.
• toLowerCase(): Convert a character string to lowercase
• toUpperCase(): Convert a character string to uppercase
• indexOf(): Provides the position of the first occurrence of a specified text in a string
• charAt(): Returns the character at the specified position in the string
• concat(): Concatenates two or more strings into one
• charCodeAt(): Returns the unicode value of a character at the specified position
• indexOf(): Provides the position of the first occurrence of a specified text in a string
• lastIndexOf(): Provides the position of the last occurrence of a specified text in a string
• slice(): Extracts part of a string and returns it as a new string
• split(): Splits a character string into an array of substrings according to a separator
• substr(): Like slice() but extracts a substring according to the number of characters specified
• substring(): Like slice() but cannot accept negative indexes
• replace(): Find and replace specific text in a string

 

Mathematical methods

• random(): Returns a random number between 0 and 1
• round(x): Round the value of x to its nearest integer
• pow(x, y): X to the power of y
• exp(x): Exponential of x
• log(x): The natural logarithm (base E) of x
• max(x, y, z,…, n): Returns the maximum
• min(x, y, z,…, n): Returns the minimum
• abs(x): Returns the absolute value of x
• sqrt(x): The square root of x
• cos(x): The cosine of x
• sin(x): The sine of x
• tan(x): The tangent of x
• ceil(x): Round the value of x to the nearest integer

 

Methods for manipulating dates/times in Javascript

• getDate(): Get the day of the month as a number (1-31)
• getDay(): The day of the week as a number (0-6)
• getFullYear(): Year as a four-digit number (yyyy)
• getHours(): Returns the hour (0-23)
• getMilliseconds(): Returns the milliseconds (0-999)
• getMinutes(): Returns the minutes (0-59)
• getMonth(): Returns the month as a number (0-11)
• getSeconds(): Get seconds (0-59)
• getTime(): Get milliseconds since January 1, 1970
• getUTCDate(): The day of the month on the date specified according to universal time.
• setDate(): Set the day as a number (1-31)
• setFullYear() : Set the year
• setHours(): Set the hour (0-23)
• setMilliseconds(): Set milliseconds (0 to 999)
• setMinutes(): Set minutes (0-59)
• setMonth(): Set month (0-11)
• setSeconds(): Set seconds (0-59)
• setTime(): Set the time (in milliseconds since January 1, 1970)
• setUTCDate(): Sets the day of the month for a specified date based on universal time

 

DOM Methods

• appendChild(): Adds a new node as the last child of a parent node.
• removeChild(): Remove a child node
• replaceChild(): Replaces a child node
• cloneNode(): Clones an HTML element
• isEqualNode(): Checks if two nodes are equal
• isSameNode(): Checks if two nodes are identical
• getAttribute(): Returns the attribute value specified in a node
• hasAttribute(): Returns true if the element has attributes, otherwise false
• removeAttribute(): Removes the attribute of the specified element
• setAttribute(): Sets or modifies the value of the specified attribute
• getElementsByTagName(): returns a collection of elements with the name of the specified tag.

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