Tutorial by Examples: co

If there are sections of code that you are considering removing or want to temporarily disable, you can comment it out with a block comment. /* Block comment around whole function to keep it from getting used. * What's even the purpose of this function? int myUnusedFunction(void) { int i =...

If MsgBox("Click OK") = vbOK Then can be used in place of If MsgBox("Click OK") = 1 Then in order to improve readability. Use Object Browser to find available VB constants. View → Object Browser or F2 from VB Editor. Enter class to search View members available ...

Object arrays are covariant, which means that just as Integer is a subclass of Number, Integer[] is a subclass of Number[]. This may seem intuitive, but can result in surprising behavior: Integer[] integerArray = {1, 2, 3}; Number[] numberArray = integerArray; // valid Number firstElement = numb...

To be able to use JDBC you need to have the JDBC driver of your database on the class path of your application. There are multiple ways to connect to a database, but the common ways are to either use the java.sql.DriverManager, or to configure and use a database specific implementation of javax.sql...

The combined assignment operators are a shortcut for an operation on some variable and subsequently assigning this new value to that variable. Arithmetic: $a = 1; // basic assignment $a += 2; // read as '$a = $a + 2'; $a now is (1 + 2) => 3 $a -= 1; // $a now is (3 - 1) => 2 $a *= 2; //...

Simple check To check if constant is defined use the defined function. Note that this function doesn't care about constant's value, it only cares if the constant exists or not. Even if the value of the constant is null or false the function will still return true. <?php define("GOOD&quo...

Constants are created using the const statement or the define function. The convention is to use UPPERCASE letters for constant names. Define constant using explicit values const PI = 3.14; // float define("EARTH_IS_FLAT", false); // boolean const "UNKNOWN" = null; // null d...

This query returns all cones with a chocolate scoop and a vanilla scoop. VANILLA, CHOCOLATE, MINT, STRAWBERRY = 1, 2, 3, 4 # constants for flavors choco_vanilla_cones = IceCream.objects.filter(scoops__contains=[CHOCOLATE, VANILLA]) Don't forget to import the IceCream model from your models.py ...

This query returns all cones with either a mint scoop or a vanilla scoop. minty_vanilla_cones = IceCream.objects.filter(scoops__contained_by=[MINT, VANILLA])

/// <summary> /// Returns the data for the specified ID and timestamp. /// </summary> /// <param name="id">The ID for which to get data. </param> /// <param name="time">The DateTime for which to get data. </param> /// <returns>A Data...

To generate an XML documentation file from documentation comments in the code, use the /doc option with the csc.exe C# compiler. In Visual Studio 2013/2015, In Project -> Properties -> Build -> Output, check the XML documentation file checkbox: When you build the project, an XML file wi...

Say you have a <textarea> and you want to retrieve info about the number of: Characters (total) Characters (no spaces) Words Lines function wordCount( val ){ var wom = val.match(/\S+/g); return { charactersNoSpaces : val.replace(/\s+/g, '').length, characte...

Horizontally vim -o file1.txt file2.txt Vertically vim -O file1.txt file2.txt You may optionally specify the number of splits to open. The following example opens two horizontal splits and loads file3.txt in a buffer: vim -o2 file1.txt file2.txt file3.txt

In normal mode: ~ inverts the case of the character under the cursor, gu{motion} lowercases the text covered by {motion}, gU{motion} uppercases the text covered by {motion} Example (^ marks the cursor position): Lorem ipsum dolor sit amet. ^ Lorem ipSum dolor sit amet. ~ Lorem...

Summary This goal is to reorganize all of your scattered commits into more meaningful commits for easier code reviews. If there are too many layers of changes across too many files at once, it is harder to do a code review. If you can reorganize your chronologically created commits into topical com...

Sometimes, you may want something to occur regardless of whatever exception happened, for example, if you have to clean up some resources. The finally block of a try clause will happen regardless of whether any exceptions were raised. resource = allocate_some_expensive_resource() try: do_stu...

Definition of Decorator as per Wikiepdia: The Decorator pattern can be used to extend (decorate) the functionality of a certain object statically, or in some cases at run-time, independently of other instances of the same class, provided some groundwork is done at design time. Decorator attach add...

Inspecting system resource usage is an efficient way to narrow down a problem on a live running application. This example is an equivalent of the traditional ps command for containers. docker top 7786807d8084 To filter of format the output, add ps options on the command line: docker top 7786807...

'Attaching to a container' is the act of starting a terminal session within the context that the container (and any programs therein) is running. This is primarily used for debugging purposes, but may also be needed if specific data needs to be passed to programs running within the container. The a...

public class Foo { private readonly IBar _iBar; public Foo(IBar iBar) { _iBar = iBar; } public void DoStuff() { _bar.DoSomething(); } } public interface IBar { void DoSomething(); }