JavaScript Cheat Sheet For Beginners

In this post you can find a cheat sheet for JavaScript for beginners, this cheat sheet helps you a lot in practicing or revising JavaScript. You must have some knowledge of JavaScript basics so that you can use this cheat sheet as a reference effectively.

Table of Contents

• Value Types
• Operators
• Assignments
• Adding To An Array
• Misc
• Event Handlers
• Comparisons
• Removing Item From An Array

Value Types

• Number Any numeric value.
• String Characters inside quote marks.
• Boolean True or False.
• Null Empty and meaningless.
• Object Any value associated with the object.
• Function Value returned by a function.

Operators

• x+y (numeric) Adds x and y together.
• x+y (string) Concatinates x and y together.
• x-y Subtracts y from x.
• x*y Multiplies x and y together.
• x/y Divides x by y.
• x%y Modulus: The remainder when x is divided y.
• x++,++x Adds one to x.
• x--,--x Subsctract one from x.
• -x Reverses the sign on x.

Assignments

• x=y Sets x to the value of y.
• x+=y Same as x = x + y.
• x-=y Same as x = x - y.
• x*=y Same as x = y.
• x/=y Same as x = x / y.
• x%=y Same as x = x % y.

Adding to an Array

• .length Adds one value to the end of an array.
• push() Adds one or more items to the end of an array.
• unshift() Adds one or more items to the beginning of an array.

Misc

• parseInt() Takes a value and tries to convert it to an integer.
• isNaN() Returns true if something is not a number.
• setTimeout() Specify that an action should occur on a particular schedule.
• Math.floor Rounds a number down.
• Math.random Generates a random number between 0 and 1.
• getElementByTagName()
• getElementById()
• getElementByClassName()
• element.innterHTM returns all the HTML between the opening and closing tags.
• element.nodeType property, returns the number of the node type.

Event Handlers

• onabort The aborted user loading the page.
• onblur The user left the object.
• onchange The user changed the object.
• onclick The user clicks an object.
• onerror The script encountered an error.
• onfocus The user made an object active.
• onload The object finished loading.
• onmouseover The cursor moved over an object.
• onmouseout The cursor moved off an object.
• onselect The user selects the contents of an object.
• onsubmit The user submitted a form.
• onunload The user left the page.
• onmove The window is moved.
• ondblclick A double click of a mouse button.
• onclick A single click (down and then up) of a mouse button.
• onreset A reset button is clicked on a form.
• onkeydown Triggered when a key is pressed down.
• onkeyup Triggered when a key is released.
• onkeypress Triggered when a key is pressed and then released.

Comparisons

• x==y Returns true if x and y are equal.
• x===y Returns true if x and y are identical.
• x!=y Returns true if x and y are not equal.
• x!==y Returns true if x and y are not identical.
• x>y Returns true if x is greater than y.
• x>=y Returns true if x is greater than or equal to y.
• x<y Returns true if x is less than y.
• x<=y RetJrns true if x is less than or equal to y.
• x&&y Returns true if both x and y are true.
• x||y Returns true if either x or y is true.
• !x RetJrns true if x is false.

Remove Item From an Array

• pop() Removes the last item from the array.
• shift() Removes the first item from the array.

📝📝 Again this is not a complete JavaScript overview, this is just a small cheat sheet from where you can take help for clearing concepts.