1. Core Programming Concepts GMETRIX

Garbage Collections

The GC.Collect method invokes garbage collection.

Garbage collection is used to free up memory when it no longer needs to be allocated to a resource.

The garbage collector usually runs continuously.

RAM

What is used within a computer to store temporary instructions

Memory

Memory stacks use a last-in, first-out (LIFO) data structure.

Memory allocation in memory stacks is static.

Memory heaps are used classes, interfaces, delegates, objects, and strings

Memory Pt.2

For memory heaps, data can be stored and removed in any order.

Memory allocation is dynamic in nature.

Memory stacks use a LIFO (Last in First Out) data structure

Data Types

The char data type uses 1 byte of memory.

The integer data type uses 4 bytes of memory.

The string data type uses a 4 byte address but can have a length of up to 2 billion bytes

If

A decision structure, which is used in all programming languages, checks for truth on a condition and takes action if it is true or not

Do. while loop

Runs a loop of code at least once and then until a condition is true or false

While Loop

Runs a loop of code while a condition is true or false but does not always run at least once

Diamond

Indicates a decision point within an app's logic

Oval

Signifies a start or end point for an app

Parallelogram

Signifies an input or output oppurtunity

Rectangle

Represents a process

Eval Expression

Typically used for an eval mathematical problem inside a string, such as for this function in Python

Adds the values

EX. eval("sum([4,6,9])") = 19.

Decision Table

An afromented table, that is used to specify conditions and actions to take on those conditions for when it is time to develop a portion of an application that requires conditional logic

Relational table

A database table that contains data other tables use as lookups for info

at Test.DataTable.AddRecord (System.String newRecord):0

at Test DataTable.Overflow.Main():20

Both exceptions are in the Test namespace.

The first statement indicates a problem with the AddRecord method inside the DataTable class.

The Main method has an error problem starting at Line 20

try-catch-finally-block

try-finally block

try-catch block

throw block

Defensive Coding

Coding in which considerations are made for unexpected situations and to where assumptions are eliminated in code

Offensive Coding

Passive Coding

Safe Coding

Try Block

A block that a try-catch-finally loop should include in the code that may throw an exception

All code that has the potential of throwing an error

Finally Block

Runs regardless whether a try block worked or a catch block was needed

Catch Block

When an error is thrown, instead of the program crashing, this block is run

Unit Test

Uses the Assert.Fail() method to fail a test that is incomplete or not implemented

Default Block

Functional Test

Logical Test

Debug Test

throw

A keyword that throws an exception and gives one an oppurtunity to display an exception message

InvalidOperationException

Is used when an excpetion is operational, not invalid or functional

IllegalOperationException

SystemException

ArgumentOutOfRangeException

1.4 Code

XHR (XML HttpRequest) is part of AJAX (Asynchronous JavaScript and XML).

The status of 200 indicates a request has succeeded.

A ready state of 4 indicates that a request for data is finished

Use asynchronous calls to invoke the web service

Return immediately and then use some other mechanism for indicating when the call actually completes. This allows web services to take the time they need to process the request without the user interface appearing to be frozen

Delegates

Events represent user actions, such as mouse clicks.

Delegate types are declared and then created.

An event resides in a delegate

Promise keyword

Used to create callbacks for both successful and failed tests in an asynchronous coding environment