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 constructor
• Cannot read property left
• Cannot read property style
• Cannot read property id
• Cannot read property editor
• Cannot read property width
• Cannot read property play
• Cannot read property keyup
• Cannot read property hasownproperty
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• Cannot read property json
• Cannot read property hide
• Cannot read property readtext
• Cannot read property webkit
• Cannot read property submit
• Cannot read property form
• Cannot read property adatasort
• Cannot read property nodetype
• Cannot read property write
• Cannot read property datatable
• Cannot read property history
• Cannot read property dataset
• Cannot read property zone
• Cannot read property error
• Cannot read property join
• Cannot read property option
• Cannot read property words
• Cannot read property top
• Cannot read property call
• Cannot read property getters
• Cannot read property innertext
• Cannot read property get
• Cannot read property jsonmodel
• Cannot read property createelement
• Cannot read property split
• Cannot read property getelementsbytagname
• Cannot read property createdocumentfragment
• Cannot read property visible
• Cannot read property x
• Cannot read property 2
• Cannot read property match
• Cannot read property html
• Cannot read property tostring
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• Cannot read property data
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• Cannot read property element
• Cannot read property appendchild
• Cannot read property prototype
• Cannot read property removechild
• Cannot read property have
• Cannot read property indexof
• Cannot read property async
• Cannot read property getattribute
• Cannot read property height

Uncaught TypeError: Cannot read property '' of null