Uncaught TypeError: Cannot read property '' of undefined
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 :
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- Cannot read property xe
- Cannot read property focus
- Cannot read property jspdf
- Cannot read property join
- Cannot read property validate
- Cannot read property type
- Cannot read property init
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- Cannot read property quesryselectorall
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- Cannot read property view
- Cannot read property style
- Cannot read property top
- Cannot read property submit
- Cannot read property touppercase
- Cannot read property createelement
- Cannot read property concat
- Cannot read property getters
- Cannot read property getitem
- Cannot read property find
- Cannot read property data
- Cannot read property 2
- Cannot read property ext
- Cannot read property play
- Cannot read property adatasort
- Cannot read property appendchild
- Cannot read property getattribute
- Cannot read property words
- Cannot read property getcontext
- Cannot read property addmethod
- Cannot read property jsonmodel
- Cannot read property each
- Cannot read property click
- Cannot read property set
- Cannot read property bind
- Cannot read property state
- Cannot read property json
- Cannot read property add
- Cannot read property play
- Cannot read property html
- Cannot read property websiteid
- Cannot read property bind
- Cannot read property hasownproperty
- Cannot read property 1
- Cannot read property 3
- Cannot read property trim
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- Cannot read property zindex
- Cannot read property helpers
- Cannot read property name
- Cannot read property reload
- Cannot read property match
- Cannot read property toggle
- Cannot read property element
- Cannot read property xrm
- Cannot read property constructor