What does "Object reference not set to an instance of an object" mean?
289
What is a NullReferenceException, and how do I fix it?
114816
Is null reference possible?
26632
Why am I getting objects printed twice?
27212
Variables might not have been initialized
146476
Java: Why aren't NullPointerExceptions called NullReferenceExceptions?
64332
avoiding null reference exceptions
37988
System.NullPointerException: Attempt to de-reference a null object:
40818
What is an IndexOutOfRangeException / ArgumentOutOfRangeException and how do I fix it?
27136
Reference: What is variable scope, which variables are accessible from where and what are "undefined variable" errors?
34819
What is the difference between an Instance and an Object?
35590
How to fix NullPointerException in Java?
66307
A field initializer cannot reference the nonstatic field, method, or property
7935
CS0120: An object reference is required for the nonstatic field, method, or property 'foo'
33243
Self-references in object literals / initializers
129333
What does IndexOutofRangeException mean?
79586
System.NullPointerException: Attempt to de-reference a null object
816
What is the difference between a variable, object, and reference?