Latch

What does it do?

Latch makes sure that a piece of code is not executed when another piece of code is executing.

This package is based on the following articles:

• http://www.minddriven.de/index.php/technology/development/design-patterns/latch-design-pattern
• http://codebetter.com/jeremymiller/2007/07/02/build-your-own-cab-12-rein-in-runaway-events-with-the-quot-latch-quot/

Examples

// Remove the event handler for the moment
someComboBox.SelectedIndexChanged -= someHandler;

// do something that would probably make someComboBox fire the SelectedIndexChanged event

// Put the event handler back
someComboBox.SelectedIndexChanged += someHandler;

This example shows a common WinForms problem which can be solved with a latch.

// Declare the Latch as field: Latch someComboBoxLatch = new Latch();

someComboBoxLatch.RunInsideLatch(() =>
{
    // do something that would probably make someComboBox fire the SelectedIndexChanged event
});

Surrounding the critical code by the latch makes sure it is only executed once. Recursive calls and StackOverflows can be avoided.

// Declare the FullLatch as field: FullLatch someLatch = new FullLatch();

someLatch.LatchAndRun(() =>
{
    // do something and make sure the latch is set
});

someLatch.RunIfNotLatched(() =>
{
    // do something that should only run when not latched
});

This way you will have full control over the latch, and you can choose which parts latch and which parts are only run if not latched.

Tools and Products Used

• Microsoft Visual Studio Community
• JetBrains Resharper
• NUnit
• FakeItEasy
• Inedo ProGet
• Icons8
• NuGet
• GitHub

Versions & Release Notes

version 1.0.3: Added .NET 8.0

version 1.0.2: Added .NET 5.0

version 1.0.1: Added .NET standard 2.0

version 1.0.0: First version (.NET Framework 4.5.2)