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

Simply put, undefined means that a variable has been declared but has not yet been given a value. This particular error is probably the easiest to understand from an undefined point of view, because undefined is not considered an object type at all (but its own undefined type instead), and properties cannot belong to only to objects in JavaScript.
This error occurs when we want to access a property on a variable whose value is undefined or null. 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).

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 contains
• Cannot read property xe
• Cannot read property apply
• Cannot read property length
• Cannot read property setstate
• Cannot read property name
• Cannot read property appendchild
• Cannot read property zone
• Cannot read property submit
• Cannot read property play
• Cannot read property view
• Cannot read property fn
• Cannot read property createelement
• Cannot read property rows
• Cannot read property use
• Cannot read property element
• Cannot read property html
• Cannot read property keyup
• Cannot read property replace
• Cannot read property error
• Cannot read property xlsx
• Cannot read property innerhtml
• Cannot read property write
• Cannot read property removechild
• Cannot read property click
• Cannot read property jspdf
• Cannot read property async
• Cannot read property touppercase
• Cannot read property then
• Cannot read property append
• Cannot read property mouse
• Cannot read property 2
• Cannot read property push
• Cannot read property destroy
• Cannot read property option
• Cannot read property y
• Cannot read property browser
• Cannot read property editor
• Cannot read property reset
• Cannot read property addmethod
• Cannot read property jsonmodel
• Cannot read property width
• Cannot read property focus
• Cannot read property setattribute
• Cannot read property classname
• Cannot read property zindex
• Cannot read property parentnode
• Cannot read property nodename
• Cannot read property height
• Cannot read property init
• Cannot read property slice
• Cannot read property document
• Cannot read property extend
• Cannot read property bind
• Cannot read property constructor
• Cannot read property keycode
• Cannot read property xhr

Uncaught TypeError: Cannot read property '' of null