var src = new Mat(@"..\..\Images\fruits.jpg", LoadMode.AnyDepth | LoadMode.AnyColor);
Cv2.ImShow("Source", src);
Cv2.WaitKey(1); // do events
Cv2.Blur(src, src, new Size(15, 15));
Cv2.ImShow("Blurred Image", src);
Cv2.WaitKey(1); // do events
// Converts the MxNx3 image into a Kx3 matrix where K=MxN and
// each row is now a vector in the 3-D space of RGB.
// change to a Mx3 column vector (M is number of pixels in image)
var columnVector = src.Reshape(cn: 3, rows: src.Rows * src.Cols);
// convert to floating point, it is a requirement of the k-means method of OpenCV.
var samples = new Mat();
columnVector.ConvertTo(samples, MatType.CV_32FC3);
for (var clustersCount = 2; clustersCount <= 8; clustersCount += 2)
{
var bestLabels = new Mat();
var centers = new Mat();
Cv2.Kmeans(
data: samples,
k: clustersCount,
bestLabels: bestLabels,
criteria:
new TermCriteria(type: CriteriaType.Epsilon | CriteriaType.Iteration, maxCount: 10, epsilon: 1.0),
attempts: 3,
flags: KMeansFlag.PpCenters,
centers: centers);
var clusteredImage = new Mat(src.Rows, src.Cols, src.Type());
for (var size = 0; size < src.Cols * src.Rows; size++)
{
var clusterIndex = bestLabels.At<int>(0, size);
var newPixel = new Vec3b
{
Item0 = (byte)(centers.At<float>(clusterIndex, 0)), // B
Item1 = (byte)(centers.At<float>(clusterIndex, 1)), // G
Item2 = (byte)(centers.At<float>(clusterIndex, 2)) // R
};
clusteredImage.Set(size / src.Cols, size % src.Cols, newPixel);
}
Cv2.ImShow(string.Format("Clustered Image [k:{0}]", clustersCount), clusteredImage);
Cv2.WaitKey(1); // do events
}
Cv2.WaitKey();
Cv2.DestroyAllWindows(); 
<!DOCTYPE html> <html> <head> <title>event propagation demo</title> </head> <body> <section> <h1>nested divs</h1> <div>one <div>child of one <div>child of child of one</div> </div> </div> </section> </body> </html>
1.window 2.document 3.<html> 4.<body> 5.<section> 6.<div>one 7.<div>child of one 8.<div>child of child of one
9.<div>child of child of one 10.<div>child of one 11.<div>one 12.<section> 13.<body> 14.<html> 15.document 16.window
<div> <button type="button">do something</button> </div> <form method="POST" action="/user"> <label>Enter user name: <input name="user"> </label> <button type="submit">submit</button> </form>
// submits the form
$('FORM').trigger('submit');
// submits the form by clicking the button
$('BUTTON[type="submit"]').trigger('click');
// focuses the text input
$('INPUT').trigger('focus');
// removes focus from the text input
$('INPUT').trigger('blur'); // submits the form
$('FORM').submit();
// submits the form by clicking the button
$('BUTTON[type="submit"]').click();
// focuses the text input
$('INPUT').focus();
// removes focus from the text input
$('INPUT').blur(); // clicks the first button - the click event does not bubble
$('BUTTON[type="button"]').triggerHandler('click'); // submits the form
document.querySelector('FORM').submit();
// submits the form by clicking the button
document.querySelector('BUTTON[type="submit"]').click();
// focuses the text input
document.querySelector('INPUT').focus();
// removes focus from the text input
document.querySelector('INPUT').blur(); var clickEvent;
if (typeof Event === 'function') {
clickEvent = new Event('click', {bubbles: false});
}
else {
clickEvent = document.createEvent('Event');
clickEvent.initEvent('click', false, true);
}
document.querySelector('BUTTON[type="button"]').dispatchEvent(clickEvent); // Triggers a custom "image-removed" element,
// which bubbles up to ancestor elements.
$libraryElement.trigger('image-removed', {id: 1}); var event = new CustomEvent('image-removed', {
bubbles: true,
detail: {id: 1}
});
libraryElement.dispatchEvent(event); var event = document.createEvent('CustomEvent');
event.initCustomEvent('image-removed', false, true, {id: 1});
libraryElement.dispatchEvent(event); var event;
// If the `CustomEvent` constructor function is not supported,
// fall back to `createEvent` method.
if (typeof CustomEvent === 'function') {
event = new CustomEvent('image-removed', {
bubbles: true,
detail: {id: 1}
});
}
else {
event = document.createEvent('CustomEvent');
event.initCustomEvent('image-removed', false, true, {
id: 1
});
}
libraryElement.dispatchEvent(event); $(window).on('resize', function() {
// react to new window size
}); // remove all resize listeners - usually a bad idea
$(window).off('resize'); var resizeHandler = function() {
// react to new window size
};
$(window).on('resize', resizeHandler);
// ...later
// remove only our resize handler
$(window).off('resize', resizeHandler); $(someElement).one('click', function() {
// handle click event
}); <button onclick="handleButtonClick()">click me</button>
buttonEl.onclick = function() {
// handle button click
}; buttonEl.addEventListener('click', function() {
// handle button click
}); window.addEventListener('resize', function() {
// react to new window size
}); var resizeHandler = function() {
// react to new window size
};
window.addEventListener('resize', resizeHandler);
// ...later
// remove only our resize handler
window.removeEventListener('resize', resizeHandler); someElement.addEventListener('click', function(event) {
// handle click event
}, { once: true }); var clickHandler = function() {
// handle click event
// ...then unregister handler
someElement.removeEventListener('click', clickHandler);
};
someElement.addEventListener('click', clickHandler); $(window).on('mousedown', function(event) {
event.preventDefault();
}); window.addEventListener('mousedown', function(event) {
event.preventDefault();
}); $someElement.on('click', function(event) {
event.stopPropagation();
}); // stop propagation during capturing phase
someElement.addEventListener('click', function(event) {
event.stopPropagation();
}, true); // stop propagation during bubbling phase
someElement.addEventListener('click', function(event) {
event.stopPropagation();
}); $someElement.on('click', function(event) {
event.stopImmediatePropagation();
}); someElement.addEventListener('click', function(event) {
event.stopImmediatePropagation();
}); $uploaderElement.trigger('uploadError', {
filename: 'picture.jpeg'
}); $uploaderParent.on('uploadError', function(event, data) {
showAlert('Failed to upload ' + data.filename);
}); // send the failed filename w/ an error event
var event = new CustomEvent('uploadError', {
bubbles: true,
detail: {filename: 'picture.jpeg'}
});
uploaderElement.dispatchEvent(event);
// ...and this is a listener for the event
uploaderParent.addEventListener('uploadError', function(event) {
showAlert('Failed to upload ' + event.detail.filename);
}); // send the failed filename w/ an error event
var event = document.createEvent('CustomEvent');
event.initCustomEvent('uploadError', true, true, {
filename: 'picture.jpeg'
});
uploaderElement.dispatchEvent(event);
// ...and this is a listener for the event
uploaderParent.addEventListener('uploadError', function(event) {
showAlert('Failed to upload ' + event.detail.filename);
}); $(window).on('load', function() {
// page is fully rendered
}); window.addEventListener('load', function() {
// page is fully rendered
}); $(document).ready(function() {
// markup is on the page
});
//or
$(function() {
// markup is on the page
}); document.addEventListener('DOMContentLoaded', function() {
// markup is on the page
}); $('IMG').on('load', function() {
// image has successfully loaded
});
$('IMG').on('error', function() {
// image has failed to load
}); document.querySelector('IMG').addEventListener('load', function() {
// image has successfully loaded
});
document.querySelector('IMG').addEventListener('error', function() {
// image has failed to load
}); $(window).on('beforeunload', function() {
return 'Are you sure you want to unload the page?';
}); window.addEventListener('beforeunload', function(event) {
var message = 'Are you sure you want to unload the page?';
event.returnValue = message;
return message;
}); C:\Program Files\Microsoft SDKs\Windows\vXYZ\bin\MdbgCore.dll
C:\Program Files\Microsoft SDKs\Windows\vXYZ\bin\NETFX 4.0 Tools\MdbgCore.dll
using System;
using System.Collections;
using System.Diagnostics;
using Microsoft.Samples.Debugging.MdbgEngine;
namespace CpuAnalyzer
{
class Program
{
static void Main(string[] args)
{
var engine = new MDbgEngine();
var processesByName = Process.GetProcessesByName("MyApp");
if (processesByName.Length == 0)
throw new InvalidOperationException("specified process not found.");
var processId = processesByName[0].Id;
var process = engine.Attach(processId);
process.Go().WaitOne();
foreach (MDbgThread thread in (IEnumerable)process.Threads)
{
foreach (MDbgFrame frame in thread.Frames)
{
if (frame == null || frame.Function == null) continue;
Console.WriteLine(frame.Function.FullName);
}
}
process.Detach().WaitOne();
}
}
}
[DllImport("kernel32.dll", CharSet = CharSet.Auto, SetLastError = true)]
public static extern bool GetThreadTimes(IntPtr handle, out long creation, out long exit, out long kernel, out long user);
for (int i = 0; i < 10; i++)
{
foreach (MDbgThread thread in (IEnumerable)process.Threads)
{
//...
}
process.Go();
Thread.Sleep(1000);
process.AsyncStop().WaitOne();
}
A .NET guideline specifies that an application should never throw a NullReferenceException. However, many applications and libraries do. The NullReferenceException is the most common exception happening. That’s why C# 8 tries to get rid of it. With C# 8, reference types are not null be default. This is a big change, and a great feature. However, what about all the legacy code? Can old libraries be used with C# 8 applications, and can C# 7 applications make use of C# 8 libraries?
This article demonstrates how C# 8 allows mixing old and new assemblies.
Here are some important fixes we’ve made in the Rider 2019.1.3 build:
Keeping up with JavaScript frameworks can be a challenge. There are a lot of them, and seemingly another one every month. How do you know which ones might be right for your project? What are their strengths and weaknesses? How do you get started?
WebGrids are fantastic when coding for a desktop layout, but what do you do when you need it mobile? Today, I analyze the WebGrid and create CSS to make the WebGrid bend to our will and make it more responsive on a mobile device.
How do you go about transferring a disk-based workload to the respective memory-optimized design? How do you process memory-optimized tables? How important for performance are natively-compiled Stored Procedures? Artemakis Artemiou comes up with a step-by-step guide to implementing an in-memory OLTP solution .
Github do not ban us from open source world
