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 document
• Cannot read property emit
• Cannot read property location
• Cannot read property style
• Cannot read property set
• Cannot read property then
• Cannot read property add
• Cannot read property browserwindow
• Cannot read property trim
• Cannot read property install
• Cannot read property filter
• Cannot read property scrolltop
• Cannot read property register
• Cannot read property hide
• Cannot read property zoneid
• Cannot read property innertext
• Cannot read property datatable
• Cannot read property props
• Cannot read property toggle
• Cannot read property ext
• Cannot read property firstchild
• Cannot read property 2
• Cannot read property locals
• Cannot read property getitem
• Cannot read property type
• Cannot read property bind
• Cannot read property constructor
• Cannot read property match
• Cannot read property fn
• Cannot read property add
• Cannot read property play
• Cannot read property id
• Cannot read property createelement
• Cannot read property getcontext
• Cannot read property append
• Cannot read property xrm
• Cannot read property write
• Cannot read property each
• Cannot read property tolowercase
• Cannot read property nodetype
• Cannot read property x
• Cannot read property findindex
• Cannot read property concat
• Cannot read property form
• Cannot read property submit
• Cannot read property queryselector
• Cannot read property adatasort
• Cannot read property formatdate
• Cannot read property value
• Cannot read property reset
• Cannot read property includes
• Cannot read property error
• Cannot read property call
• Cannot read property play
• Cannot read property zindex
• Cannot read property parentnode
• Cannot read property state

Uncaught TypeError: Cannot read property '' of null