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 option
• Cannot read property removechild
• Cannot read property jsonmodel
• Cannot read property add
• Cannot read property includes
• Cannot read property form
• Cannot read property createdocumentfragment
• Cannot read property files
• Cannot read property target
• Cannot read property foreach
• Cannot read property firstchild
• Cannot read property bind
• Cannot read property concat
• Cannot read property keycode
• Cannot read property props
• Cannot read property add
• Cannot read property addmethod
• Cannot read property tostring
• Cannot read property msie
• Cannot read property ext
• Cannot read property map
• Cannot read property createelement
• Cannot read property emit
• Cannot read property have
• Cannot read property hasattribute
• Cannot read property nodename
• Cannot read property join
• Cannot read property history
• Cannot read property match
• Cannot read property each
• Cannot read property y
• Cannot read property defaultview
• Cannot read property error
• Cannot read property width
• Cannot read property quesryselectorall
• Cannot read property remove
• Cannot read property version
• Cannot read property extend
• Cannot read property trim
• Cannot read property append
• Cannot read property websiteid
• Cannot read property scrolltop
• Cannot read property formatdate
• Cannot read property click
• Cannot read property queuedepthsort
• Cannot read property locals
• Cannot read property data
• Cannot read property id
• Cannot read property checked
• Cannot read property install
• Cannot read property apply
• Cannot read property value
• Cannot read property split
• Cannot read property which
• Cannot read property json
• Cannot read property preventdefault
• Cannot read property readtext

Uncaught TypeError: Cannot read property '' of null