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 focus
• Cannot read property rows
• Cannot read property getelementsbyclassname
• Cannot read property history
• Cannot read property id
• Cannot read property constructor
• Cannot read property getcontext
• Cannot read property document
• Cannot read property jsonmodel
• Cannot read property play
• Cannot read property sort
• Cannot read property jquery
• Cannot read property innertext
• Cannot read property type
• Cannot read property words
• Cannot read property bridge
• Cannot read property register
• Cannot read property x
• Cannot read property split
• Cannot read property 1
• Cannot read property jspdf
• Cannot read property validate
• Cannot read property location
• Cannot read property websiteid
• Cannot read property height
• Cannot read property reduce
• Cannot read property write
• Cannot read property style
• Cannot read property 3
• Cannot read property datatable
• Cannot read property createdocumentfragment
• Cannot read property version
• Cannot read property adatasort
• Cannot read property xhr
• Cannot read property zindex
• Cannot read property formatdate
• Cannot read property createelement
• Cannot read property xe
• Cannot read property files
• Cannot read property get
• Cannot read property nodetype
• Cannot read property option
• Cannot read property browser
• Cannot read property keyboard
• Cannot read property apply
• Cannot read property target
• Cannot read property getattribute
• Cannot read property call
• Cannot read property add
• Cannot read property checked
• Cannot read property length
• Cannot read property tostring
• Cannot read property which
• Cannot read property getelementsbytagname
• Cannot read property 2
• Cannot read property nodename
• Cannot read property dataset

Uncaught TypeError: Cannot read property '' of null