*Note that in general, IDE&#39;s like Visual Studio will markup a comment in the context of the current language, by selecting the text you wish to turn into a comment, and then using the &lt;kbd&gt;Ctrl&lt;/kbd&gt;+&lt;kbd&gt;K&lt;/kbd&gt; &lt;kbd&gt;Ctrl&lt;/kbd&gt;+&lt;kbd&gt;C&lt;/kbd&gt; shortcut, or if you are using Resharper / Intelli-J style shortcuts, then &lt;kbd&gt;Ctrl&lt;/kbd&gt;+&lt;kbd&gt;/&lt;/kbd&gt;.*

*Server side Comments:*

**Razor .cshtml**  

[Like so:](http://weblogs.asp.net/scottgu/asp-net-mvc-3-server-side-comments-with-razor)

&lt;!-- language: lang-c#--&gt;

    @* Comment goes here *@

**.aspx**  
For those looking for the older `.aspx` view (and Asp.Net WebForms) [server side comment syntax](http://msdn.microsoft.com/en-us/library/4acf8afk(v=vs.100).aspx):

&lt;!-- language: lang-c#--&gt;

    &lt;%-- Comment goes here --%&gt;

*Client Side Comments*

**HTML Comment**

&lt;!-- language: lang-html--&gt;

    &lt;!-- Comment goes here --&gt;


**Javascript Comment**

&lt;!-- language: lang-js--&gt;

    // One line Comment goes Here
    /* Multiline comment
       goes here */

As OP mentions, although not displayed on the browser, client side comments will *still be generated* for the page / script file on the server and downloaded by the page over HTTP, which unless removed (e.g. minification), will *waste I/O*, and, since the comment can be viewed by the user by viewing the page source or intercepting the traffic with the browser&#39;s Dev Tools or a tool like Fiddler or Wireshark, can also *pose a security risk*, hence the preference to use server side comments on server generated code (like MVC views or .aspx pages).

This comment syntax should work for you:

    @* enter comments here *@


Is there any way on [GitHub][1] to list all commits made by a single author, in the browser (neither locally, e.g. via `git log`, nor via the API)?

Clicking on a user name in the list of commits (Commit History) simply leads to that user&#39;s profile page. Examining the GitHub UI and searching (Google, StackOverflow) does not reveal a way to do this.


  [1]: http://github.com/

GitHub - List commits by author

I have a table that is created using ng-repeat. I want to add validation to each element in the table. The problem is that each input cell has the same name as the cell above and below it. I attempted to use the `{{$index}}` value to name the inputs, but despite the string literals in HTML appearing correct, it is now working.


Here is my code as of now:
      
    &lt;tr ng-repeat=&quot;r in model.BSM &quot;&gt;
	   &lt;td&gt;
		  &lt;input ng-model=&quot;r.QTY&quot; class=&quot;span1&quot; name=&quot;QTY{{$index}}&quot; ng-pattern=&quot;/^[\d]*\.?[\d]*$/&quot; required/&gt;
	      &lt;span class=&quot;alert-error&quot; ng-show=&quot;form.QTY{{$index}}.$error.pattern&quot;&gt;&lt;strong&gt;Requires a number.&lt;/strong&gt;&lt;/span&gt;
		  &lt;span class=&quot;alert-error&quot; ng-show=&quot;form.QTY{{$index}}.$error.required&quot;&gt;&lt;strong&gt;*Required&lt;/strong&gt;&lt;/span&gt;
	   &lt;/td&gt;
    &lt;/tr&gt;

I have tried removing the `{{}}` from index, but that does not work either. As of now, the validation property of the input is working correctly, but the error message is not displayed.

Anyone have any suggestions?

**Edit:** In addition to the great answers below, here is a blog article that covers this issue in more detail: http://www.thebhwgroup.com/blog/2014/08/angularjs-html-form-design-part-2/

How to validate inputs dynamically created using ng-repeat, ng-show (angular)

How to write a comment in a MVC view, that won&#39;t be transmitted to the final HTML (i.e.,to browser, to response). One can make a comment with:

&lt;!-- language: lang-none --&gt;

    &lt;!--&lt;a href=&quot;/&quot;&gt;My comment&lt;/a&gt; --&gt;

but, it is visible in the page source code in browser.

Is it possible to leave comments in &#39;.cshtml&#39; files only for internal use?

How to write a comment in a Razor view?

How to write a comment in a MVC view, that won't be transmitted to the final HTML (i.e.,to browser, to response). One can make a comment with:

<pre><code class="hljs language-php-template">&#x3C;!--&#x3C;a href="/">My comment&#x3C;/a> -->
</code></pre>
but, it is visible in the page source code in browser.
Is it possible to leave comments in '.cshtml' files only for internal use?

I have a `byte[]` and I&#39;m looking for the most efficient way to base64 encode it.  

The problem is that the built in .Net method `Convert.FromBase64CharArray` requires a `char[]` as an input, and converting my `byte[]` to a `char[]` just to convert it again to a base64 encoded array seems pretty stupid.

Is there any more direct way to do it?

[[EDIT:]] I&#39;ll expaling what I want to acheive better - I have a `byte[]` and I need to  return a new base64 encoded `byte[]`

An efficient way to Base64 encode a byte array?

For a payment provider, I need to calculate a hash-based message authentication code, using HMAC-SHA256. That is causing me quite a bit of trouble.

The payment provider gives two examples of orrectly calculated authentication code in pseudo-code. All keys are in hex.

###Method 1 

    key = 57617b5d2349434b34734345635073433835777e2d244c31715535255a366773755a4d70532a5879793238235f707c4f7865753f3f446e633a21575643303f66
    message = &quot;amount=100&amp;currency=EUR&quot;
    MAC = HMAC-SHA256( hexDecode(key), message )
    result = b436e3e86cb3800b3864aeecc8d06c126f005e7645803461717a8e4b2de3a905

###Method 2

    message = &quot;amount=100&amp;currency=EUR&quot;
    Ki = 61574d6b157f757d02457573556645750e0341481b127a07476303136c005145436c7b46651c6e4f4f040e1569464a794e534309097258550c17616075060950
    Ko = 0b3d27017f151f17682f1f193f0c2f1f64692b227178106d2d096979066a3b2f2906112c0f760425256e647f032c2013243929636318323f667d0b0a1f6c633a
    MAC = SHA256( hexDecode(Ko) + SHA256( hexDecode(Ki) + message ) )
    result = b436e3e86cb3800b3864aeecc8d06c126f005e7645803461717a8e4b2de3a905

I tried to write the code to do this, after doing some research, but I keep coming up with different results.





    private static void Main(string[] args)
        {
            var key = &quot;57617b5d2349434b34734345635073433835777e2d244c31715535255a366773755a4d70532a5879793238235f707c4f7865753f3f446e633a21575643303f66&quot;;
            var ki = &quot;61574d6b157f757d02457573556645750e0341481b127a07476303136c005145436c7b46651c6e4f4f040e1569464a794e534309097258550c17616075060950&quot;;
            var ko = &quot;0b3d27017f151f17682f1f193f0c2f1f64692b227178106d2d096979066a3b2f2906112c0f760425256e647f032c2013243929636318323f667d0b0a1f6c633a&quot;;
            var mm = &quot;amount=100&amp;currency=EUR&quot;;

            var result1 = CalcHMACSHA256Hash(HexDecode(key), mm);

            var result2 = CalcSha256Hash(string.Format(&quot;{0}{1}&quot;, HexDecode(ko), CalcSha256Hash(HexDecode(ki) + mm)));

            Console.WriteLine(&quot;Expected: b436e3e86cb3800b3864aeecc8d06c126f005e7645803461717a8e4b2de3a905&quot;);
            Console.WriteLine(&quot;Actual 1: &quot; + result1);
            Console.WriteLine(&quot;Actual 2: &quot; + result2);

            Console.WriteLine(&quot;------------------------------&quot;);
            Console.ReadKey();

        }

        private static string HexDecode(string hex)
        {
            var sb = new StringBuilder();
            for (int i = 0; i &lt;= hex.Length - 2; i += 2)
            {
                sb.Append(Convert.ToString(Convert.ToChar(Int32.Parse(hex.Substring(i, 2), System.Globalization.NumberStyles.HexNumber))));
            }
            return sb.ToString();
        }

        private static string CalcHMACSHA256Hash(string plaintext, string salt)
        {
            string result = &quot;&quot;;
            var enc = Encoding.Default;
            byte[]
            baText2BeHashed = enc.GetBytes(plaintext),
            baSalt = enc.GetBytes(salt);
            System.Security.Cryptography.HMACSHA256 hasher = new HMACSHA256(baSalt);
            byte[] baHashedText = hasher.ComputeHash(baText2BeHashed);
            result = string.Join(&quot;&quot;, baHashedText.ToList().Select(b =&gt; b.ToString(&quot;x2&quot;)).ToArray());
            return result;
        }


        public static string CalcSha256Hash(string input)
        {
            SHA256 sha256 = new SHA256Managed();
            byte[] sha256Bytes = Encoding.Default.GetBytes(input);
            byte[] cryString = sha256.ComputeHash(sha256Bytes);
            string sha256Str = string.Empty;
            for (int i = 0; i &lt; cryString.Length; i++)
            {
                sha256Str += cryString[i].ToString(&quot;x2&quot;);
            }
            return sha256Str;
        }


And this is the result I get:

    Expected: b436e3e86cb3800b3864aeecc8d06c126f005e7645803461717a8e4b2de3a905
    Actual 1: 421ce16f2036bb9f2a3770c16f01e9220f0232d45580584ca41768fd16c15fe6
    Actual 2: 290f14398bf8c0959dfc963e2fd9c377534c6fec1983025d2ab192382f132b92

So with none of the two methods, I can get the result the provider example wants.

**What am I missing here? Is it encoding? Is my hexDecode screwed up?**

Test tool from payment provider: http://tech.dibs.dk/dibs_api/other_features/hmac_tool/

PHP sample code: http://tech.dibspayment.com/dibs_api/other_features/mac_calculation/

Calculating HMACSHA256 using c# to match payment provider example

Recently I came across an interview question to create a algorithm in any language which should do the following

1. Read 1 terabyte of content 
2. Make a count for each reoccuring word in that content 
3. List the top 10 most frequently occurring words

Could you let me know the best possible way to create an algorithm for this?

Edit:

OK, let&#39;s say the content is in English. How we can find the top 10 words that occur most frequently in that content? My other doubt is, if purposely they are giving unique data then our buffer will expire with heap size overflow. We need to handle that as well.

Parsing one terabyte of text and efficiently counting the number of occurrences of each word

I am currently writing a desktop application, but I cannot seem to get my head around what to use when redirecting someone to a new section of the application.

My options appear to be

* Window
* Page
* UserControl

but I don&#39;t understand what the difference between them is, and when I should use each one.

Could someone explain the differences for me, and give an example of what situations/applications you may use each one for?

Window vs Page vs UserControl for WPF navigation?

Usually, I get this error:
(The &quot;service name&quot; service on Local Computer started and then stopped. Some services stop automatically if they are not in use by other service or programs) when there&#39;s something wrong with my code, like non-existing drive paths, etc. The windows service will not start.

I have a windows service that backs up folder/files, to a location if it reached the size limit. Details are all provide by an XML Configuration that the windows service reads on start. I have a separate windows forms that has a button that does exactly what my windows service&#39;s onstart is doing. I use my windows forms for debugging the code before I put it in my windows service.

When I start my windows forms. It does what it suppose to do. When I put my code in the windows service OnStart() method the error showed up.

Here&#39;s my code:

    protected override void OnStart(string[] args)
    {

        private static string backupConfig = @&quot;D:\LogBackupConfig\backupconfig.xml&quot;;
        private static string serviceStat = @&quot;D:\LogBackupConfig\Status.txt&quot;;
        private static string fileFolderStat = @&quot;D:\LogBackupConfig\FileFolderStat.txt&quot;;

        protected override void OnStart(string[] args)
        {
            if (File.Exists(backupConfig))
            {
                FileSystemWatcher watcher = new FileSystemWatcher();
                XmlTextReader reader = new XmlTextReader(backupConfig);

                XmlNodeType type;
                List&lt;string&gt; listFile = new List&lt;string&gt;();
                string fileWatch = &quot;&quot;;
                
                //this loop is for reading XML elements and assigning to variables
                while (reader.Read())
                {
                    type = reader.NodeType;
                    if (type == XmlNodeType.Element)
                    {
                        if (reader.Name == &quot;File&quot;)
                        {
                            reader.Read();
                            fileWatch = reader.Value;
                        }
                        else if (reader.Name == &quot;Folder&quot;)
                        {
                            reader.Read();
                            fileWatch = reader.Value;
                        }
                    }
                }
                reader.Close();

                watcher.Path = fileWatch;
                watcher.Filter = &quot;*.*&quot;;
                
                //this loop reads whether the service will watch a file/folder
                XmlTextReader reader1 = new XmlTextReader(backupConfig);
                while (reader1.Read())
                {
                    type = reader1.NodeType;
                    if (type == XmlNodeType.Element)
                    {
                        if (reader1.Name == &quot;File&quot;)
                        {
                            watcher.IncludeSubdirectories = false;
                            watcher.Changed += new FileSystemEventHandler(OnChangedFile);
                        }
                        else if (reader1.Name == &quot;Folder&quot;)
                        {
                            watcher.IncludeSubdirectories = true;
                            watcher.Changed += new FileSystemEventHandler(OnChangedFolder);
                        }
                    }
                }
                reader1.Close();

                watcher.EnableRaisingEvents = true;

            }
            else
            {
                StreamWriter sw = new StreamWriter(serviceStat, true);
                sw.WriteLine(&quot;File not found. Please start the Log Backup UI first.&quot;);
                sw.Close();
            }
        }

I don&#39;t know what keeps the windows service not starting, the windows form simulator worked fine. What seems to be the problem?

UPDATE:
After many trials I&#39;ve noticed that using only a folder directory (w/out file), the windows service doesn&#39;t work. When I replaced the fileWatch variable with a specific file (including its directory), the windows service started. When I changed it back to a folder location, it didn&#39;t work. What I think is that folder locations doesn&#39;t work in a filewatcher.

When I tried creating a new windows service that watches a folder location, it worked.. However, when I tried the same location in my original windows service, it didn&#39;t work! I was mindf$#*ed! It seems that I have to create a new windows service and build the installer everytime I place a new code/function.. This way I can keep track where I get an error.

Windows service on Local Computer started and then stopped error

    @Html.HiddenFor(model =&gt; model.title, new { id= &quot;natureOfVisitField&quot;, @value = &#39;@Model.title&#39;})

it doesen&#39;t work! how to set the value?

HTML.HiddenFor value set

&gt; An expression tree may not contain a call or invocation that uses
&gt; optional arguments

    return this.RedirectToAction&lt;MerchantController&gt;(x =&gt; x.Edit(merchantId));

Where edit had a second, nullable argument.

Why is this?



An expression tree may not contain a call or invocation that uses optional arguments

I am using ASP.NET MVC 3 to build a web application.

What I am trying to do is pass values between two controllers, though there are many ways to do this I am particular interested in using `TempData` for this.

	public ActionResult Action1()
	{
		string someMessage;
		Test obj = SomeOperation();
		if(obj.Valid)
		{
			someMessage = obj.UserName;
		}
		else
		{
			someMessage = obj.ModeratorName;
		}
		
		TempData[&quot;message&quot;] = someMessage;
		
		return RedirectToAction(&quot;Index&quot;);
	}

	public ActionResult Index()
	{
		ViewBag.Message = TempData[&quot;message&quot;]

		return View();
	}

So is the use of `TempData` here correct ? I mean under best programming practices is this correct way of using `TempData` ?

In what real time cases should `TempData` be used ?

**Note :** I have gone through the following links

- https://stackoverflow.com/questions/1500402/when-to-use-tempdata-vs-session-in-asp-net-mvc
- http://www.gregshackles.com/2010/07/asp-net-mvc-do-you-know-where-your-tempdata-is/

Thanks

Using Tempdata in ASP.NET MVC - Best practice

I use HTTP `PUT` and `DELETE` in my ASP.NET MVC3 application. When I run it in local, every thing works correctly; But when I publish the application to the server, these methods do not work. 

Are there any special settings for enable a web server to support `PUT` and `DELETE` requests? I&#39;m using shared hosting with IIS 7.5.

**UPDATE:**

I enable `PUT` and `DELETE` requests in `IIS manager`. `PUT` command work fine. But `DELETE` still not works. I create requests by `jQuery`:

I&#39;m in this page:

    http://domain.com/dashboard/edit-site/103323/links/

and my ajax call is:

    $.ajax({
        // url: same as page-url,
        cache: false,
        type: &#39;DELETE&#39;,
        data: { linkid: $(link).data(&quot;linkid&quot;) },
        beforeSend: function () {
            // doing something in UI
        },
        complete: function () {
            // doing something in UI
        },
        success: function (data) {
            // doing something in UI
        },
        error: function () {
            // doing something in UI
        }
    });

This will create a request like this:

    Accept: */*
    Content-Type: application/x-www-form-urlencoded; charset=UTF-8
    Origin: http://domain.com
    Referer: http://domain.com/dashboard/edit-site/103323/links/
    User-Agent: Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.1 (KHTML, like Gecko) Chrome/21.0.1180.89 Safari/537.1
    X-Requested-With: XMLHttpRequest

With this **`Form Data`**:

    linkid:104044

How do I enable HTTP PUT and DELETE for ASP.NET MVC in IIS?

I am attempting to run an application in IIS8 that has the following in the config:

    &lt;modules runAllManagedModulesForAllRequests=&quot;true&quot; /&gt;

IIS8 is giving me an error that says...

&gt; This configuration section cannot be used at this path. This happens
&gt; when the section is locked at a parent level. Locking is either by
&gt; default (overrideModeDefault=&quot;Deny&quot;), or set explicitly by a location
&gt; tag with overrideMode=&quot;Deny&quot; or the legacy allowOverride=&quot;false&quot;.

I&#39;m guessing by the error and a quick SO search that there is some higher level security setting that&#39;s preventing that line from being allowed. Any ideas?

IIS8 Win8 and runAllManagedModulesForAllRequests=&quot;true&quot;

How would I generate a select list, where the text field, is made up of two or more text columns, eg: Where I have a Description and Rate field in my database, I want to combine these to show:

    Large--&#163;200
    Medium--&#163;150
    Small--&#163;100

Controller code is:
     
     var stands = db.Stands.Where(s =&gt; s.ExhibitorID == null).ToList();
     ViewBag.StandID = new SelectList(stands,&quot;StandID&quot;, &quot;Description&quot; + &quot;-- &#163;&quot; + &quot;Rate&quot;);
   
...and my view is (currently):

        &lt;div class=&quot;editor-field&quot;&gt; 
            @Html.DropDownList(&quot;StandID&quot;, &quot;--Select--&quot;) 
        &lt;/div&gt; 

...but the &quot;Description&quot; + &quot;-- &#163;&quot; + &quot;Rate&quot;); won&#39;t run:

&gt; DataBinding:
&gt; &#39;System.Data.Entity.DynamicProxies.Stand_63F8C9F623B3C0E57D3008A57081AFCD9C39E1A6B79B0380B60840F1EFAE9DB4&#39;
&gt; does not contain a property with the name &#39;Description--&#163;Rate&#39;.


Thanks for any help,

Mark

MVC SelectList combining multiple columns in text field

    @{
        int i = 0;
    }
    
    @helper Text() {
        &lt;input type=&quot;text&quot; name=&quot;Ans[@i].Text&quot; /&gt;
    }

`i` is not accessible in helper. How to access it?

Access global page variable in helper

I&#39;ve got a property in my model called `Promotion` that its type is a flag enum called `UserPromotion`. Members of my enum have display attributes set as follows:

    [Flags]
    public enum UserPromotion
    {
        None = 0x0,

        [Display(Name = &quot;Send Job Offers By Mail&quot;)]
        SendJobOffersByMail = 0x1,

        [Display(Name = &quot;Send Job Offers By Sms&quot;)]
        SendJobOffersBySms = 0x2,

        [Display(Name = &quot;Send Other Stuff By Sms&quot;)]
        SendPromotionalBySms = 0x4,

        [Display(Name = &quot;Send Other Stuff By Mail&quot;)]
        SendPromotionalByMail = 0x8
    }

Now I want to be able to create say a `ul` in my view to show the selected values of my `Promotion` property. This is what I have done so far but the problem is that how can I get the display names here?

    &lt;ul&gt;
        @foreach (int aPromotion in @Enum.GetValues(typeof(UserPromotion)))
        {
            var currentPromotion = (int)Model.JobSeeker.Promotion;
            if ((currentPromotion &amp; aPromotion) == aPromotion)
            {
            &lt;li&gt;Here I don&#39;t know how to get the display attribute of &quot;currentPromotion&quot;.&lt;/li&gt;
            }
        }
    &lt;/ul&gt;

How to get the Display Name Attribute of an Enum member via MVC Razor code?

I have the following project structure:

- /Views/Shared/_Layout;

- /Areas/Area1/Views/ControllerName/Index;

...

- /Areas/AreaN/Views/ControllerName/Index.

Is there any way to force all areas to use the **_Layout** as a **base layout**?

Is there any way to do it without adding the **_ViewStart** file (for example, via the routing configuration)?

**See Also:**

[How do I specify different Layouts in the ASP.NET MVC 3 razor ViewStart file?][1]


  [1]: https://stackoverflow.com/questions/5161380/

Force all Areas to use same Layout

I believe I read somewhere there is a setting in one of the project files that will allow you to compile the `.cshtml` files when building your Visual Studio project. 

Just getting started with `MVC/Razor/Query` Mobile, and am getting annoyed with the &quot;Error loading page&quot; when I have an error in a code block inside a `.cshtml` file


How to compile cshtml before runtime

I&#39;ve recently upgraded to Visual Studio 2012 and haven&#39;t have any problems except for the fact that comments beginning with &quot;//todo&quot; no longer show up in the task list. I have absolutely no idea on where to start looking for a solution to this problem as all of the keywords are too general.

I came across other similar questions where the answer was that the file wasn&#39;t open containing the //todo comment, but that is not the case for me. My todo comments do not show up even when the file is open in front of me.

Todo tasks not appearing in the Task List in visual studio 2012

I have recently started using `//` to &quot;comment&quot; out single lines of CSS code. I understand that I am not actually commenting out the line; I am just breaking it (I should use `/* ... */`), but it has the same effect. The line is then terminated by the `;` and the following code works fine.

I could delete it, but often I prefer not to in case I want to put it back in later or see what I had been using if I come back to it.

Example:

    li{
        float:left;
        //list-style-type:none;
        text-indent:0px;
    }

Can I get away with this, or is it likely to cause me problems?


Is it bad practice to comment out single lines of CSS with //?

I&#39;ve been writing some batch files, and I ran into [this user guide](http://www.tacktech.com/display.cfm?ttid=307), which has been quite informative. One thing it showed me was that lines can be commented not just with `REM`, but also with `::`. It says:

&gt; Comments in batch code can be made by using a double-colon, this is better than using the REM command because labels are processed before redirection symbols. `::&lt;remark&gt;` causes no problems but `rem &lt;remark&gt;` produces errors. 

Why then, do most guides and examples I see use the `REM` command? Does `::` work on all versions of Windows?

Which comment style should I use in batch files?

In github, you can comment on lines in a commit. Is there a way to comment on a line, while viewing a file in a branch, without having a particular commit?

Comment on a line in Github without a commit?

In the VBA editor of Office (&lt;kbd&gt;ALT&lt;/kbd&gt; + &lt;kbd&gt;F11&lt;/kbd&gt;), how do you comment or uncomment a block of code?

Content Type	Original Author	Original Content on Stackoverflow
Question	horgh	View Question on Stackoverflow
Solution 1 - C#	StuartLC	View Answer on Stackoverflow
Solution 2 - C#	sobering	View Answer on Stackoverflow

How to write a comment in a Razor view?

C# Problem Overview

C# Solutions

Solution 1 - C#

Solution 2 - C#

How to validate inputs dynamically created using ng-repeat, ng-show (angular)

GitHub - List commits by author

Attributions