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This example hides the red box (border) if the checkbox is not checked by making use of an IValueConverter. Note: The BooleanToVisibilityConverter used in the example below is a built-in value converter, located in the System.Windows.Controls namespace. XAML: <Window x:Class="StackOverflo...

In order to work with bindings in WPF, you need to define a DataContext. The DataContext tells bindings where to get their data from by default. <Window x:Class="StackOverflowDataBindingExample.MainWindow" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation&q...

INotifyPropertyChanged is an interface used by binding sources (i.e. the DataContext) to let the user interface or other components know that a property has been changed. WPF automatically updates the UI for you when it sees the PropertyChanged event raised. It is desirable to have this interface im...

You can bind to a property on a named element, but the named element must be in scope. <StackPanel> <CheckBox x:Name="MyCheckBox" IsChecked="True" /> <TextBlock Text="{Binding IsChecked, ElementName=MyCheckBox}" /> </StackPanel>

You can bind to a property of an ancestor in the visual tree by using a RelativeSource binding. The nearest control higher in the visual tree which has the same type or is derived from the type you specify will be used as the binding's source: <Grid Background="Blue"> <Grid ...

PS > Get-Member -InputObject $anObjectInstance This will return all members of the type instance. Here is a part of a sample output for String instance TypeName: System.String Name MemberType Definition ---- ---------- ---------- Clone ...

The Django template system has built-in tags and filters, which are functions inside template to render content in a specific way. Multiple filters can be specified with pipes and filters can have arguments, just as in variable syntax. {{ "MAINROAD 3222"|lower }} # mainroad 3222 {{ 10...

If you need to add an attribute through razor that has a - (hyphen) in the name you cannot simply do @Html.DropDownListFor(m => m.Id, Model.Values, new { @data-placeholder = "whatever" }) it will not compile. data-* attributes are valid and common in html5 for adding extra values t...

F# Interactive, is a REPL environment that lets you execute F# code, one line at a time. If you have installed Visual Studio with F#, you can run F# Interactive in console by typing "C:\Program Files (x86)\Microsoft SDKs\F#\4.0\Framework\v4.0\Fsi.exe". On Linux or OS X, the command is fsh...

The official style guide is located on the homepage and generally goes for: readability (instead of compactness) ease of modification clean diffs This means that, for example, this: homeDirectory : String homeDirectory = "/root/files" evaluate : Boolean -> Bool evalua...

You can diff UTF-16 encoded files (localization strings file os iOS and macOS are examples) by specifying how git should diff these files. Add the following to your ~/.gitconfig file. [diff "utf16"] textconv = "iconv -f utf-16 -t utf-8" iconv is a program to convert differe...

The random() function can be used to generate pseudo-random numbers: void setup() { Serial.begin(9600); } void loop() { long randomNumber = random(500); // Generate a random number between 0 and 499 Serial.println(randomNumber); randomNumber = random(100, 1000); // Genera...

If it is important for a sequence of numbers generated by random() to differ, it is a good idea to specify a seed with randomSeed(): void setup() { Serial.begin(9600); // If analog pin 0 is left unconnected, analogRead(0) will produce a // different random number each time the ...

With TypeScript 1.8 it becomes possible for a type parameter constraint to reference type parameters from the same type parameter list. Previously this was an error. function assign<T extends U, U>(target: T, source: U): T { for (let id in source) { target[id] = source[id]; ...

composer update composer update will update our dependencies as they are specified in composer.json. For example, if our project uses this configuration: "require": { "laravelcollective/html": "2.0.*" } Supposing we have actually installed the 2.0.1 version ...

Below are the operators that can be overloaded in classes, along with the method definitions that are required, and an example of the operator in use within an expression. N.B. The use of other as a variable name is not mandatory, but is considered the norm. OperatorMethodExpression+ Addition__add...

name:"john doe"~1 Searches for multiple terms within a specific term distance (~1), i.e will find text containing john anonymous doe but not john second name doe

name:john Searches for a single term (joe) in a single field (name)

+firstname:john +surname:doe Matches documents where firstname is john and surname is doe. + predix indicates that the search term must occur (AND). +firstname:john -surname:doe Matches documents where firstname is john and surname is not doe. - predix indicates that the search term must not occu...

name:"john doe" Searches for multiple terms in specific order.