`PropertyExpression` is internal

You should cast it to `System.Linq.Expressions.MemberExpression` instead, as suggested in [this post][1].

  [1]: https://social.msdn.microsoft.com/Forums/en-US/ab528f6a-a60e-4af6-bf31-d58e3f373356/resolving-propertyexpressions-and-fieldexpressions-in-a-custom-linq-provider?forum=linqprojectgeneral

We have an Angular + Ionic + Cordova project with multiple devs that we&#39;d like to manage cordova plugin dependencies for. We are using [Cordova CLI 5+][1], and when manually running the install commands (e.g. `cordova plugin add cordova-plugin-camera`), a new line gets added to the `cordovaPlugins` section of the `package.json` file. Here&#39;s what the finished product looks like:

    &quot;cordovaPlugins&quot;: [
      &quot;cordova-plugin-camera&quot;,
      &quot;cordova-plugin-console&quot;,
      &quot;cordova-plugin-contacts&quot;,
      &quot;cordova-plugin-device&quot;,
      &quot;cordova-plugin-dialogs&quot;,
      &quot;cordova-plugin-file&quot;,
      &quot;cordova-plugin-geolocation&quot;,
      &quot;cordova-plugin-media&quot;,
      &quot;cordova-plugin-media-capture&quot;,
      &quot;cordova-plugin-network-information&quot;,
      &quot;cordova-plugin-splashscreen&quot;,
      &quot;cordova-plugin-statusbar&quot;,
      &quot;cordova-plugin-vibration&quot;,
      &quot;com.ionic.keyboard&quot;
    ]

That&#39;s all great, except we can&#39;t find any way for dev #2 to npm install those plugins - instead, he has to run the commands individually, which then adds a duplicate line to `package.json`, dirtying the repository. We are sure there must be a command to install these, but can&#39;t find it. Can anyone shed some light?


  [1]: http://cordova.apache.org/docs/en/5.0.0/guide_cli_index.md.html

Manage cordova plugins with npm + package.json

I&#39;m wondering what the best way is in Java 8 to work with all the values of an enum. Specifically when you need to get all the values and add it to somewhere, for example, supposing that we have the following enum:

    public enum Letter {
     A, B, C, D;
    }

I could of course do the following:

    for (Letter l : Letter.values()) {
        foo(l);
    }

But, I could also add the following method to the enum definition:

    public static Stream&lt;Letter&gt; stream() {
        return Arrays.stream(Letter.values());
    }

And then replace the for from above with:

    Letter.stream().forEach(l -&gt; foo(l));

Is this approach OK or does it have some fault in design or performance? Moreover, why don&#39;t enums have a stream() method?

Java 8 way to work with an enum

I try to write a simple example using Expressions, but have a strange bug: I can&#39;t use `PropertyExpression` at compile time. When I write it I get an error and it doesn&#39;t compile 
![enter image description here][1]
But in runtime at breakpoint I can write 

    var runtimeBody = (System.Linq.Expressions.PropertyExpression)body2;

and it works, and casts as expected. Framework 4.5.1 is selected as target. 


  [1]: http://i.stack.imgur.com/AqvG8.png

PropertyExpression is missing

I try to write a simple example using Expressions, but have a strange bug: I can't use <code>PropertyExpression</code> at compile time. When I write it I get an error and it doesn't compile
<img src="http://i.stack.imgur.com/AqvG8.png" alt="enter image description here">
But in runtime at breakpoint I can write
<pre><code class="hljs language-ini">var runtimeBody = (System.Linq.Expressions.PropertyExpression)body2;
</code></pre>
and it works, and casts as expected. Framework 4.5.1 is selected as target.

I&#39;m using HttpResponseMessage class as a response from an AJAX call which is returning JSON data from a service.  When I pause execution after the AJAX call comes back from the service, I see this class contains a Content property which is of type System.Net.Http.StreamContent.   

If I inspect in the browser I see the network call being made successfully and the JSON data as the response.  I&#39;m just wondering why I cannot see the returned JSON text from within Visual Studio?  I searched throughout this System.Net.Http.StreamContent object and see no data. 

    public async Task&lt;HttpResponseMessage&gt; Send(HttpRequestMessage request) {
    	var response = await this.HttpClient.SendAsync(request);
    	return response;
    }

How to read HttpResponseMessage content as text

I just downloaded Visual Studio Code and my Intellisense is not automatically working.

The two settings that control this seem to be set correctly:

    &quot;editor.quickSuggestions&quot;: true,
    &quot;editor.suggestOnTriggerCharacters&quot;: true,

I do get an Intellisense menu when i start typing and press &quot;CTRL + Space&quot;, but this gives me a list of everything and not things specifically for my object.

What am i doing wrong?

Intellisense not automatically working VSCode

I&#39;m getting suddenly a strange error while debugging. Up to now the variable in the watch windows has been shown correctly. Now I am getting always the error message in the watch windows:

&gt; The function evaluation requires all threads to run

I am not able to check any variable anymore. I am not explicit working with threads. What can I do to get it working again?

I disabled already as mentioned in some forums the function: &quot;Enable property Evaluation and other implicit function Calls&quot; in the option window of the debugger. But without success, then I am getting the error: 

&gt; Error Implicit Function evaluation disabled by the user

Visual Studio during Debugging: The function evaluation requires all threads to run

I am given an absolute URI that contains a query string. I&#39;m looking to safely append a value to the query string, and change an existing parameter.

I would prefer not to tack on `&amp;foo=bar`, or use regular expressions, URI escaping is tricky. Rather I want to use a built-in mechanism that I know will do this correctly and handle the escaping.

I&#39;ve [found](https://stackoverflow.com/a/17096289/492405) [a](https://stackoverflow.com/q/10232034/492405) [ton](https://stackoverflow.com/questions/11956948/easiest-way-to-parse-querystring-formatted-data) of answers that all use `HttpUtility`. However this being ASP.NET Core, there is no more System.Web assembly anymore, thus no more `HttpUtility`.

What is the appropriate way to do this in ASP.NET Core while targeting the core runtime?

Parse and modify a query string in .NET Core

I have been searching for the differences between 2 pairs above but haven&#39;t found any articles explaining clearly about it as well as when to use one or another.

So what is the difference between `SaveChanges()` and `SaveChangesAsync()`?&lt;br&gt;
And between `Find()` and `FindAsync()`?

On server side, when we use `Async` methods, we also need to add `await`. Thus, I don&#39;t think it is asynchronous on server side.

Does it only help to prevent the UI blocking on client side browser? Or are there any pros and cons between them?

Entity Framework SaveChanges() vs. SaveChangesAsync() and Find() vs. FindAsync()

.NET 4.5 has a new namespace [System.Collections.Immutable](https://msdn.microsoft.com/en-us/library/system.collections.immutable(v=vs.111).aspx)

&gt; This package provides collections that are thread safe and guaranteed to never change their contents, also known as immutable collections.

I&#39;m confused. Isn&#39;t the thread safety problem already solved by the [ReadOnlyCollection](https://msdn.microsoft.com/en-us/library/ms132474%28v=vs.110%29.aspx) class? Why use [ImmutableList](https://msdn.microsoft.com/en-us/library/dn467185%28v=vs.111%29.aspx) instead?

* * * 

I know there&#39;s also an [IReadOnlyList *interface*](https://msdn.microsoft.com/en-us/library/hh192385%28v=vs.110%29.aspx). That doesn&#39;t solve the thread safety problem implicitly, because other threads may edit the object by another interface.


Why use ImmutableList over ReadOnlyCollection?

Recently I used `dot Trace profiler` to find the bottlenecks in my application.

Suddenly, I have seen that in most of the places which are taking more time and more `CPU` usage to is `SNINativeMethodWrapper.SNIReadSyncOverAsync()` which is called by `Execute` reader method of `ADO.Net`, I don&#39;t know why it&#39;s taking more time. 

If I run the same query in `SQL server` it&#39;s running very fast. 

 1. Does anybody know why it&#39;s taking more time?
 2. What is the alternative for this `ADO.Net` method?

SNIReadSyncOverAsync Performance issue

I was looking at the new features for Visual Studio 2015 and Shared Project came up a lot but I don&#39;t understand how it is different to using a Class Library or a Portable Class Library. Can anyone explain? 

**Edit:** Shared Project is a new feature in Visual Studio 2015 and is different to a Portable Class Library. I understand what a Portable Class Library is. What I&#39;m trying to understand is how a Shared Project differs to a Class Library. See link below. 

http://www.c-sharpcorner.com/UploadFile/7ca517/shared-project-an-impressive-features-of-visual-studio-201/

What is the difference between a Shared Project and a Class Library in Visual Studio 2015?

I am developing a TCP client to connect OpenSSL server with the certificate authentication. I have using .crt and .key files shared by server team. These certificates are generated by OpenSSL commands.

I am using [`SslStream`](https://msdn.microsoft.com/en-us/library/system.net.security.sslstream%28v=vs.85%29.aspx) object to authenticate the Tcp client by calling [`SslStream.AuthenticateAsClient`](https://msdn.microsoft.com/en-us/library/system.net.security.sslstream.beginauthenticateasclient%28v=vs.85%29.aspx) method by passing server `IP`, [`SslProtocols.Ssl3`](https://msdn.microsoft.com/en-us/library/system.security.authentication.sslprotocols%28v=vs.85%29.aspx) and `X509CertificateCollection`.

I am getting the following error:

&gt; Authentication failed because the remote party has closed the transport stream


Authentication failed because remote party has closed the transport stream

The default value for `int` is 0 , for `string` is &quot;&quot; and for `boolean` it is false. Could someone please clarify what the default value for `guid` is?  


What is the default value for Guid?

The `invokedynamic` instruction is used to help the VM determine the method reference at runtime instead hardwiring it at compile time. 

This is useful with dynamic languages where the exact method and argument types aren&#39;t known until runtime. But that isn&#39;t the case with Java lambdas. They are translated to a static method with well defined arguments. And this method can be invoked using `invokestatic`.

So then what is the need of `invokedynamic` for lambdas, especially when there is a performance hit?


Why are Java 8 lambdas invoked using invokedynamic?

I have two list and i want filter thoose elements which are both list contains. And i want to do this with lambda expression.

Users getName and Clients getUserName both are return with String.

Here is my sample code:

    List&lt;Client&gt; clients = new ArrayList&lt;&gt;();
    List&lt;User&gt; users = new ArrayList&lt;&gt;();
    List&lt;Client&gt; results = new ArrayList&lt;&gt;();

    for (Client user : users) {
        for(Client client: clients){
            if(user.getName().equals(client.getUserName())){
                result.add(client);
            }
        }
    }

Java 8 Lambda filter by Lists

Modifying a local variable in `forEach` gives a compile error:

**Normal**

        int ordinal = 0;
        for (Example s : list) {
            s.setOrdinal(ordinal);
            ordinal++;
        }

**With Lambda**

        int ordinal = 0;
        list.forEach(s -&gt; {
            s.setOrdinal(ordinal);
            ordinal++;
        });

Any idea how to resolve this?

Modifying local variable from inside lambda

I needed to have a lambda expression of the functional interface `Runnable` that did nothing. I used to have a method

    private void doNothing(){
        //Do nothing
    }

and then use `this::doNothing`. But I&#39;ve found an even shorter way to do this.

Lambda that does absolutely nothing

I am trying  to follow [this example](https://stackoverflow.com/questions/4478636/stdremove-if-lambda-not-removing-anything-from-the-collection) to use a lambda with `remove_if`. Here is my attempt:

    int flagId = _ChildToRemove-&gt;getId();
	auto new_end = std::remove_if(m_FinalFlagsVec.begin(), m_FinalFlagsVec.end(), 
            [](Flag&amp; device) { 
                return device.getId() == flagId; 
            });
    
    m_FinalFlagsVec.erase(new_end, m_FinalFlagsVec.end());


but this fails to compile:

    error C3493: &#39;flagId&#39; cannot be implicitly captured because no default capture mode has been specified

How can I include the outside parameter, `flagId`,  in the lambda expression?

Error: variable &quot;cannot be implicitly captured because no default capture mode has been specified&quot;

After reading [this answer][2] about undefined behavior and sequence points, I wrote a small program:

    #include &lt;stdio.h&gt;

    int main(void) {
      int i = 5;
      i = (i, ++i, 1) + 1;
      printf(&quot;%d\n&quot;, i);
      return 0;
    }

The output is `2`. Oh God, I didn&#39;t see the decrement coming! What is happening here?

Also, while compiling the above code, I got a warning saying:

&gt; px.c:5:8: warning: left-hand operand of comma expression has no effect&lt;br&gt;
&gt;
&gt;       [-Wunused-value]   i = (i, ++i, 1) + 1;
&gt;                             ^

Why? But probably it will be automatically answered by the answer of my first question.

  [1]: https://stackoverflow.com/questions/30605380/bash-usr-bin-hydra-pmi-proxy-no-such-file-or-directory
  [2]: https://stackoverflow.com/a/4176333/2411320


What does i = (i, ++i, 1) + 1; do?

The following code is wrong (see it [on ideone](http://ideone.com/vSoRsM)):

    public class Test
    {
    	public static void Main()
    	{
    	    int j = 5;
    	    (j++);      // if we remove the &quot;(&quot; and &quot;)&quot; then this compiles fine.
    	}
    }

&gt; error CS0201: Only assignment, call, increment, decrement, await, and
&gt; new object expressions can be used as a statement

1. Why does the code compile when we remove the parentheses?
2. Why does it not compile with the parentheses?
3. Why was C# designed that way?

Why was the statement (j++); forbidden?

While reading the example code provided by Texas Instruments for their [SensorTag][1] I came across the following snippet.

    void SensorTagIO_processCharChangeEvt(uint8_t paramID) { 
        ...

        if (!!(ioValue &amp; IO_DATA_LED1)) {
            PIN_setOutputValue(hGpioPin, Board_LED1, Board_LED_ON);
        } else {
            PIN_setOutputValue(hGpioPin, Board_LED1, Board_LED_OFF);
        }
        
        if (!!(ioValue &amp; IO_DATA_LED2)) {
            PIN_setOutputValue(hGpioPin, Board_LED2, Board_LED_ON);
        } else {
            PIN_setOutputValue(hGpioPin, Board_LED2, Board_LED_OFF);
        }
        
        if (!!((ioValue &amp; IO_DATA_BUZZER))) {
            Clock_start(buzzClockHandle);
        }
        ...
    }

The declaration is like this (in the same file). 

    #define IO_DATA_LED1   0x01
    static uint8_t ioValue;

Does `if (!!(ioValue &amp; IO_DATA_LED1))` offer any advantage over `if (ioValue &amp; IO_DATA_LED1)`? 


  [1]: http://www.ti.com/sensortag

Content Type	Original Author	Original Content on Stackoverflow
Question	Alex Zhukovskiy	View Question on Stackoverflow
Solution 1 - C#	Sébastien Sevrin	View Answer on Stackoverflow

PropertyExpression is missing

C# Problem Overview

C# Solutions

Solution 1 - C#

Java 8 way to work with an enum

Manage cordova plugins with npm + package.json

Attributions