JSON is a highlight of JavaScript. It can use elegant and concise code to initialize objects and arrays. It is also a text-based data definition, which is more semantic than symbol separation and more concise than XML. As a result, more and more JS developers are using it for data transmission and storage.
JS arrays have built-in many useful methods to facilitate data query and filtering. For example, we have a bunch of data:Copy codeThe Code is as follows:Var heros = [// Name = intelligence ===
response
C # There are encapsulated HTTP request and response classes HttpWebRequest and HttpWebResponse, so it is much easier to implement.
To improve the download efficiency, we can use multiple concurrent requests to download resources from multiple URLs at the same time. A simple method is to use asynchronous requests.
You can use the following method to control the number of concurrency:
1 private void DispatchWork () 2 {3 if (_ stop) // determine whether to abort download 4 {5 return; 6}
synchronize threads. Next let's try:
Class Program {static int num = 1; static void Main (string [] args) {Stopwatch stopWatch = new Stopwatch (); // start the timer stopWatch. start (); ThreadStart threadStart = new ThreadStart (Run); for (int I = 0; I
Execution result:
In this way, simple synchronization is implemented. Compared with the above Code, only a line of code (thread. join ();), previously mentioned the Join () method is used to block the current thread until the previous thread e
further:Must the lock object be placed in Foo?Typing @ sync for each interface function is still annoying and repetitive. If one is missing, it will still cause inexplicable runtime errors. Why not concentrate on it?To solve the preceding disadvantages, the code for version 3rd is as follows:
class DecorateClass(object): def decorate(self): for name, fn in self.iter(): if not self.filter(name, fn): continue self.operate(name, fn)class LockerDecorator(DecorateClass): def __init__(self, o
returns immediately; The queue mechanism is used between threads, and the direct mechanism is used within threads, but these default mechanisms can be changed in connect.1 view plaincopy to Clipboardprint?2//textdevice.h3 #ifndef Textdevice_h4 #define Textdevice_h5 #include 6 #include 7 #include 8 class Textdevice:public Qthread {9 Q_objectPublic:Textdevice ();The void run ();void Stop ();Public Slots:void Write (const qstring text);Private:M_count int;Qmutex M_mutex;19};#endif//Textdevice_h21s
StaticEventWaitHandle handler =NewAutoResetEvent (false); Public Static voidEat () {Thread.Sleep ( the); } Public Static voidEat_withset () {Thread.Sleep ( the); Handler. Set (); //a sub-thread sends a signal to be done; } Public Static voidEat_withlock () {Console.WriteLine ("Shackles begin"); Lock(Locker) {Thread.Sleep ( the);//Suppose we have a lot of things to do here;//The effect is very good;} Console.WriteLine ("Shackle
Using System;Using System.Collections.Generic;Using System.Linq;Using System.Text;Using System.Threading.Tasks;Namespace Singleleton{public class Singleleton{Declare a static variable to store the entity3. To save an instance of the created instance that defines a static variable to saveprivate static Singleleton _instance = null;4. Create an object for the yoke to prevent multiple instances of multithreading creationprivate static Object locker = new
variable, so done is output only once:DoneThe static variable provides a different way to share variables in the thread, here is an example:Class ThreadTest {static bool done,//static fields is shared between all threadsstatic void Main () {new Thread (Go). Start (); Go ();} static void Go () {if (!done) {done = true; Console.WriteLine ("Done"); }}}Here the output is not very sure, it looks like to output two times done, in fact, it is impossible. Let's exchange the order of Go,Class ThreadTes
, conversely, its shortcomings!) The output is actually indeterminate: it may (though improbable), "done", can be printed two times. However, if we change the order of instructions in the Go method, the chance of "done" being printed two times will rise substantially, such as:Static void Go () { if (!done) {Console.WriteLine ("done"true;}} The problem is that when a thread is judging the if block, just the other thread is executing the WriteLine statement--before it sets done to true. The remed
= True;}}} Output Result:Output of two "done", the event was made two times. Due to the lack of control concurrency, there is a thread security problem that cannot guarantee the state of the data.To solve this problem, you need to use a lock (lock, also known as an exclusive lock or mutex). Using the lock statement, you can guarantee that shared data can only be accessed by one thread at a time. The lock's data object requires an object of a reference type that cannot be null, so the lock ob
.") Result:%s% (func.__name__, ret))return retReturn _deco@decoDef MyFunc (A, B):Print ("MyFunc (%s,%s) called."% (A, b))Return a+b@decoDef MYFUNC2 (A, B, c):Print ("Myfunc2 (%s,%s,%s) called."% (A, B, c))Return A+b+cMyFunc (1, 2)MyFunc (3, 4)MYFUNC2 (1, 2, 3)MYFUNC2 (3, 4, 5)
Seventh step: Let the adorner take the parameter
#-*-CODING:GBK-*-"Example 7: On the basis of example 4, let the adorner take a parameter,Compared with the previous example, there is a layer of packaging in the outer lay
recommend CTRL + SHIFT + H to bulk replace the lock code (write a regular)
/ Will: The namespace of the CDL is removed, so that you do not have to guide namespace.
Once a deadlock occurs, it will hit the Cdl::_showgetlocktimeout methodThen print out the contents of the Cdl.dumps () to see which cdl.checkdl are currently deadlocked.Dumps is very detailed, specific can also according to their own needs to locker information to make adjustments. identi
* Refer to this article please indicate from blog.csdn.net/wtz1985
In the previous article, I have explained the implementation of simple locks in multiple threads, but at the end of the day, I mentioned a problem, that is, if you are inserting in a linked list, the operation of the query, if only a simple lock, can not be achieved. So the "recursive lock" comes to the world.
Perhaps some people see recursion these two words, a bit silly eye, actually also nothing, simple introduction, is to car
Tags: connect connection string Nested instance sum Oracle get one exception1. Using Assembly Oracle.ManagedDataAccess.dllUsing Oracle.ManagedDataAccess.Client;Using System.Configuration;Namespace ClassLibrary1{///Database connection Practice single-instance mode/// public class Oracledbconect{private static oracleconnection con = null;private static Object obj = new Object ();///Define public static property instance, external call/// public static OracleConnection Instance{Get{When the first t
Isingletonsender:ibasesender {}public class singletonsender:isingletonsender{public void Send (ST Ring message) = = Console.WriteLine ($ "{GetHashCode ()} {message}");} Class program{private static readonly object locker = new Object (); static void Main (string[] args) {var serviceprovider = new Servicecollection (). Addtransient
The program output looks like this:
Through what we can learn,
In the same or different scopes, servi
Because the experimental server needs to be provided remotely to the development of children's shoes to use, these two days toss a bit of Linux Remote Desktop, in this record summary. Server System for Lubuntu 16.04Telnet to Linux scenario one: simple use of--X11VNCSingle-user case, using X11VNC is the simplest method, the detailed setup process can be viewed in this article, which provides an automatic configuration script. Don't repeat it here.Precautions:
At the end of the script the
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