JavaScript Error: Uncaught TypeError: Cannot read property '' of null

JavaScript TypeError is returned when an operand or argument passed to a function is incompatible with the type expected by that operator or function. This error occurs in the browser when you read a property or call a method on an undefined object.
There are a few variations of this error depending on the property you are trying to access. Sometimes instead of undefined it will output null: Uncaught TypeError: Cannot read property '' of null

Cannot read property '' of undefined

Cannot read property '' of null

Undefined means that a variable has been declared, but the value of that variable has not yet been defined. In JavaScript, there are Undefined (type), undefined (value) and undefined (variable).
This error occurs when you try to call a method or try to access a property of a variable that does not exist (is not an object). This error occurs when we want to access a property on a variable whose value is undefined or null.

Null vs. Undefined in JavaScript The value "undefined" indicates that a variable has been declared, but no value has been assigned. On the other hand, "null" refers to a non-existent object, which basically means "empty" or "nothing". These are two values ​​generally used to indicate the absence of something. Also, undefined and null are two distinct types: undefined is a type itself (undefined) while null is an object.

Other Javascript errors :

• Cannot read property id
• Cannot read property browser
• Cannot read property files
• Cannot read property datatable
• Cannot read property slice
• Cannot read property query
• Cannot read property version
• Cannot read property add
• Cannot read property formatdate
• Cannot read property findindex
• Cannot read property foreach
• Cannot read property split
• Cannot read property classname
• Cannot read property data
• Cannot read property destroy
• Cannot read property bind
• Cannot read property removechild
• Cannot read property webkit
• Cannot read property appendchild
• Cannot read property keyboard
• Cannot read property locals
• Cannot read property element
• Cannot read property style
• Cannot read property contains
• Cannot read property apply
• Cannot read property hide
• Cannot read property state
• Cannot read property reset
• Cannot read property length
• Cannot read property keycode
• Cannot read property tolowercase
• Cannot read property setstate
• Cannot read property extend
• Cannot read property 2
• Cannot read property click
• Cannot read property nodename
• Cannot read property readtext
• Cannot read property set
• Cannot read property target
• Cannot read property prototype
• Cannot read property jquery
• Cannot read property hasownproperty
• Cannot read property indexof
• Cannot read property words
• Cannot read property y
• Cannot read property 10
• Cannot read property getattribute
• Cannot read property constructor
• Cannot read property queryselector
• Cannot read property form
• Cannot read property scrolltop
• Cannot read property push
• Cannot read property 3
• Cannot read property rows
• Cannot read property match
• Cannot read property mouse
• Cannot read property innertext

Uncaught TypeError: Cannot read property '' of null