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 find
• Cannot read property getters
• Cannot read property apply
• Cannot read property 2
• Cannot read property then
• Cannot read property document
• Cannot read property appendchild
• Cannot read property emit
• Cannot read property queuedepthsort
• Cannot read property fn
• Cannot read property data
• Cannot read property style
• Cannot read property getelementsbytagname
• Cannot read property use
• Cannot read property length
• Cannot read property visible
• Cannot read property zone
• Cannot read property join
• Cannot read property append
• Cannot read property defaultview
• Cannot read property match
• Cannot read property mouse
• Cannot read property trim
• Cannot read property click
• Cannot read property setattribute
• Cannot read property write
• Cannot read property uid
• Cannot read property destroy
• Cannot read property left
• Cannot read property x
• Cannot read property extend
• Cannot read property readtext
• Cannot read property push
• Cannot read property files
• Cannot read property document
• Cannot read property query
• Cannot read property option
• Cannot read property textcontent
• Cannot read property parentnode
• Cannot read property dataset
• Cannot read property zindex
• Cannot read property indexof
• Cannot read property focus
• Cannot read property y
• Cannot read property helpers
• Cannot read property browserwindow
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• Cannot read property datatable
• Cannot read property locals
• Cannot read property formatdate
• Cannot read property bind
• Cannot read property toggle
• Cannot read property contains
• Cannot read property msie
• Cannot read property hasownproperty
• Cannot read property map
• Cannot read property xhr

Uncaught TypeError: Cannot read property '' of null