Tutorial by Examples: t

Getting Started with CardView

CardView is a member of the Android Support Library, and provides a layout for cards. To add CardView to your project, add the following line to your build.gradle dependencies. compile 'com.android.support:cardview-v7:25.1.1' A number of the latest version may be found here In your layout you ...

Android • CardView

Joining an array of strings into a new one

var parts = new[] { "Foo", "Bar", "Fizz", "Buzz"}; var joined = string.Join(", ", parts); //joined = "Foo, Bar, Fizz, Buzz"

C# Language • Common String Operations

Specifying structure using XPath expressions

SELECT 'XPath example' AS 'head/title', 'This example demonstrates ' AS 'body/p', 'https://www.w3.org/TR/xpath/' AS 'body/p/a/@href', 'XPath expressions' AS 'body/p/a' FOR XML PATH('html') <html> <head> <title>XPath example</title> &...

Microsoft SQL Server • FOR XML PATH

Padding a string to a fixed length

string s = "Foo"; string paddedLeft = s.PadLeft(5); // paddedLeft = " Foo" (pads with spaces by default) string paddedRight = s.PadRight(6, '+'); // paddedRight = "Foo+++" string noPadded = s.PadLeft(2); // noPadded = "Foo" (original string...

C# Language • Common String Operations

Establish a web socket connection

var wsHost = "ws://my-sites-url.com/path/to/web-socket-handler"; var ws = new WebSocket(wsHost);

JavaScript • WebSockets

Working with string messages

var wsHost = "ws://my-sites-url.com/path/to/echo-web-socket-handler"; var ws = new WebSocket(wsHost); var value = "an example message"; //onmessage : Event Listener - Triggered when we receive message form server ws.onmessage = function(message) { if (message === value...

JavaScript • WebSockets

Padding the output

String can be formatted to accept a padding parameter that will specify how many character positions the inserted string will use : ${value, padding} NOTE: Positive padding values indicate left padding and negative padding values indicate right padding. Left Padding A left padding of 5 (a...

C# Language • String Interpolation

Link to a page on the same site

You can use a relative path to link to pages on the same website. <a href="/example">Text Here</a> The above example would go to the file example at the root directory (/) of the server. If this link was on http://example.com, the following two links would bring the user...

HTML • Anchors and Hyperlinks

Logical connective of values

5.1 .some and .every allow a logical connective of Array values. While .some combines the return values with OR, .every combines them with AND. Examples for .some [false, false].some(function(value) { return value; }); // Result: false [false, true].some(function(value) { return value...

JavaScript • Arrays

Class lambdas and capture of this

A lambda expression evaluated in a class' member function is implicitly a friend of that class: class Foo { private: int i; public: Foo(int val) : i(val) {} // definition of a member function void Test() { auto lamb = [](Foo &foo, int val) ...

C++ • Lambdas

Simulating variable-length lookbehind with \K

Some regex flavors (Perl, PCRE, Oniguruma, Boost) only support fixed-length lookbehinds, but offer the \K feature, which can be used to simulate variable-length lookbehind at the start of a pattern. Upon encountering a \K, the matched text up to this point is discarded, and only the text matching th...

Regular Expressions • Lookahead and Lookbehind

Newlines and control characters

A newline can be included in a single-string or double-quoted string. Note that backslash-newline does not result in a newline, the line break is ignored. newline1=' ' newline2=" " newline3=$'\n' empty=\ echo "Line${newline1}break" echo "Line${newline2}break" ...

Bash • Quoting

Double quotes for variable and command substitution

Variable substitutions should only be used inside double quotes. calculation='2 * 3' echo "$calculation" # prints 2 * 3 echo $calculation # prints 2, the list of files in the current directory, and 3 echo "$(($calculation))" # prints 6 Outside of doubl...

Bash • Quoting

Quoting literal text

All the examples in this paragraph print the line !"#$&'()*;<=>? @[\]^`{|}~ A backslash quotes the next character, i.e. the next character is interpreted literally. The one exception is a newline: backslash-newline expands to the empty string. echo \!\"\#\$\&\'\*\;\...

Bash • Quoting

Installing a TypeHandler

The above type handler can be installed into SqlMapper using the AddTypeHandler method. SqlMapper.AddTypeHandler<IHtmlString>(new IHtmlStringTypeHandler()); Type inference allows you to omit the generic type parameter: SqlMapper.AddTypeHandler(new IHtmlStringTypeHandler()); There's als...

Dapper.NET • Type Handlers

Bitwise AND

The & operator will perform a binary AND, where a bit is copied if it exists in both operands. That means: # 0 & 0 = 0 # 0 & 1 = 0 # 1 & 0 = 0 # 1 & 1 = 1 # 60 = 0b111100 # 30 = 0b011110 60 & 30 # Out: 28 # 28 = 0b11100 bin(60 & 30) # Out: 0b11100