از زمانیکه موتور پردازشی جاوا اسکریپت فایرفاکس در نگارش 18 تغییر کرده (Faster JavaScript performance via IonMonkey compiler)، این مرورگر دچار مصرف بالای CPU به صورت مداوم شده ....
اشتراکها
<script src="js/kendo.web.min.js" type="text/javascript"></script>
<script type="text/javascript" src='<%: ResolveClientUrl("~/path....") %>'></script>
<script type="text/javascript"> $(document).ready(function () { PopupForm.ShowForm({ renderFormUrl : "/postreply/renderreplyform", ..... }); }); </script>
<script src='<%= ResolveUrl("~/Scripts/jquery-1.4.1.js")%>' type="text/javascript" />
using System.Collections.Generic; using System.Diagnostics; using System.Linq; namespace SignalR04.Common { public class Counter { public string Name { set; get; } public float Value { set; get; } } public class PerformanceCounterProvider { private readonly List<PerformanceCounter> _counters = new List<PerformanceCounter>(); public PerformanceCounterProvider() { _counters.Add(new PerformanceCounter("Processor", "% Processor Time", "_Total", readOnly: true)); _counters.Add(new PerformanceCounter("Memory", "Pages/sec", readOnly: true)); _counters.Add(new PerformanceCounter("PhysicalDisk", "% Disk Time", "_Total", readOnly: true)); } public IList<Counter> GetResults() { return _counters.Select(c => new Counter { Name = c.CategoryName, Value = c.NextValue() }).ToList(); } } }
using System.Threading; using Microsoft.AspNet.SignalR; using ThreadTimer = System.Threading.Timer; namespace SignalR04.Common { public class PerformanceCounterHub : Hub { private ThreadTimer _threadTimer; //keep it alive private readonly PerformanceCounterProvider _perfService = new PerformanceCounterProvider(); public PerformanceCounterHub() { _threadTimer = new ThreadTimer(timerCallback, null, Timeout.Infinite, 1000); _threadTimer.Change(dueTime: 1000, period: 2000); } private void timerCallback(object state) { var results = _perfService.GetResults(); this.Clients.All.newCounters(results); } } }
<html xmlns="http://www.w3.org/1999/xhtml"> <head runat="server"> <title></title> <script src="Scripts/jquery-1.6.4.min.js" type="text/javascript"></script> <script src="Scripts/jquery.signalR-1.1.3.min.js" type="text/javascript"></script> <script type="text/javascript" src='<%= ResolveClientUrl("~/signalr/hubs") %>'></script> <script src="Scripts/smoothie.js" type="text/javascript"></script> </head> <body> <form id="form1" runat="server"> <div> <div> <h2>Processor</h2> <canvas id="Processor" width="800" height="100"></canvas> </div> <div> <h2>Memory</h2> <canvas id="Memory" width="800" height="100"></canvas> </div> <div> <h2>PhysicalDisk</h2> <canvas id="PhysicalDisk" width="800" height="100"></canvas> </div> </div> </form> <script type="text/javascript"> var ChartEntry = function (name) { var self = this; self.name = name; self.chart = new SmoothieChart({ millisPerPixel: 50, labels: { fontSize: 15} }); self.timeSeries = new TimeSeries(); self.chart.addTimeSeries(self.timeSeries, { lineWidth: 3, strokeStyle: "#00ff00" }); }; ChartEntry.prototype = { addValue: function (value) { var self = this; self.timeSeries.append(new Date().getTime(), value); }, start: function () { var self = this; self.canvas = document.getElementById(self.name); self.chart.streamTo(self.canvas); } }; $(function () { $.connection.hub.logging = true; var performanceCounterHub = $.connection.performanceCounterHub; var charts = []; performanceCounterHub.client.newCounters = function (updatedCounters) { $.each(updatedCounters, function (index, updateCounter) { var entry; $.each(charts, function (idx, chart) { if (chart.name == updateCounter.Name) { entry = chart; return; } }); if (!entry) { entry = new ChartEntry(updateCounter.Name); charts.push(entry); entry.start(); } entry.addValue(updateCounter.Value); }); }; $.connection.hub.start(); }); </script> </body> </html>
let s = Symbol();
let s1 = Symbol("some description");
let firstName = Symbol(); let person = { lastName: "Vahid", [firstName]: "N", }; // person.lastName = "Vahid" // person[firstName] = "N"
let names = []; for(var p in person) { names.push(p); }
var numbers = [1, 2, 3];
numbers[Symbol.iterator];
var numbersIterator = numbers[Symbol.iterator](); numbersIterator.next(); // Result: Object {value: 1, done: false} numbersIterator.next(); // Result: Object {value: 2, done: false} numbersIterator.next(); // Result: Object {value: 3, done: false} numbersIterator.next(); // Result: Object {value: undefined, done: true}
function Words(str) { this._str = str; }
Words.prototype[Symbol.iterator] = function() { var re = /\S+/g; var str = this._str; return { next: function() { var match = re.exec(str); if (match) { return {value: match[0], done: false}; } return {value: undefined, done: true}; } } };
var helloWorld = new Words("Hello world"); for (var word of helloWorld) { console.log(word); } // Result: "Hello" // Result: "world"
InvalidCastExceptio
internal class Employee { ... } public sealed class Program { public static void Main() { // بدون ذکر نام والد تبدیل صورت میگیرد Object o = new Employee(); // برای تبدیل والد به یکی از مشتقات آن نیاز است // نوع آن به طور صریح ذکر گردد // در بعضی زبانهای مثل ویژوال بیسیک نیازی به ذکر آن نیست Employee e = (Employee) o; } }
Object o = new Object(); Boolean b1 = (o is Object); // b1 is true. Boolean b2 = (o is Employee); // b2 is false.
پی نوشت :در این بررسی اگر شیء نال باشد، مقدار برگشتی همیشه false است. چون به هیچ نوعی قابل تبدیل نیست.نحوهی استفادهی از کلمه کلیدی is در این تبدیل به شکل زیر است:
if (o is Employee) { Employee e = (Employee) o; }
Employee e = o as Employee; if (e != null) { ..... }
System.Text
public sealed class Program { public static void Main() { System.IO.FileStream fs = new System.IO.FileStream(...); System.Text.StringBuilder sb = new System.Text.StringBuilder(); } }
using System.IO; // Try prepending "System.IO." using System.Text; // Try prepending "System.Text." public sealed class Program { public static void Main() { FileStream fs = new FileStream(...); StringBuilder sb = new StringBuilder(); } }
using Microsoft; using Dotnettips ; public sealed class Program { public static void Main() { Widget w = new Widget();// An ambiguous reference } }
'Widget' is an ambiguous reference between 'Microsoft.Widget' and 'Dotnettips.Widget
using Microsoft; using Dotnettips; public sealed class Program { public static void Main() { Dotnettips.Widget w = new Dotnettips.Widget(); // Not ambiguous } }
using Microsoft; using Dotnettips; using DotnettipsWidget = Dotnettips.Widget; public sealed class Program { public static void Main() { DotnettipsWidget w = new DotnettipsWidget (); // No error now } }
<CustomControls:FrameFactory x:Name="ActiveScreen" HorizontalContentAlignment="Stretch" VerticalContentAlignment="Stretch" NavigationUIVisibility="Hidden" Grid.Column="1" Margin="0" />
/// <summary> /// تغییر مشخصات کاربر جاری /// </summary> [PageAuthorization(AuthorizationType.FreeForAuthenticatedUsers)] public partial class ChangeProfile
<Button Style="{DynamicResource MetroCircleButtonStyle}" Height="55" Width="55" Command="{Binding DoNavigate}" CommandParameter="\Views\UserInfo\ChangeProfile.xaml" Margin="2"> <Rectangle Width="28" Height="17.25"> <Rectangle.Fill> <VisualBrush Stretch="Fill" Visual="{StaticResource appbar_user_tie}" /> </Rectangle.Fill> </Rectangle> </Button>
public abstract class BaseViewModel : DataErrorInfoBase, INotifyPropertyChanged, IViewModel