How to create image link in ASP.NET MVC?

@Html.ActionLink("buttontext", "actionName", "controllerName", null, new { @class="alinkimage" })

CSS definition:

a.classname
{
background: url(../Images/image.gif) no-repeat top left;
display: block;
width: 150px;
height: 150px;
}

How to encode url in ASP.NET MVC 3

HttpContext.Current.Server.UrlEncode(text)

How to create an event into Google Calendar by url?

Goto google page:
http://support.google.com/calendar/answer/3033039
Fill related information, then get following link:
http://www.google.com/calendar/event?action=TEMPLATE&text=Event%20Title&dates=20140426T040000Z/20140426T050000Z&details=Event_detail&location=Event_location&trp=false&sprop=&sprop=name

The best interface is no interface

http://www.cooper.com/journal/2012/08/the-best-interface-is-no-interface.html/

How to validate Canada postal code by regular expression?

^[ABCEGHJKLMNPRSTVXY]\d[A-Z]\d[A-Z]\d$
Code example for ASP.NET webform  RegularExpression validator

<asp:RegularExpressionValidator ID="RegularExpressionValidator1" runat="server" ErrorMessage="*" ControlToValidate="TextBoxPostalCode" ValidationExpression="^[ABCEGHJKLMNPRSTVXY]\d[A-Z]\d[A-Z]\d$"></asp:RegularExpressionValidator>

Basic Concept
http://en.wikipedia.org/wiki/Regular_expression
Online Regular Expression tester
http://www.regular-expressions.info/javascriptexample.html

How to get line number in textarea by Javascript?

textarea.value.split(/\r?\n|\r/).length + 1

Facebook Platform's OAuth 2.0 Protocol and ASP.NET MVC

http://amirrajan.net/Blog/asp-mvc-and-facebook-single-sign-on

How to convert ASP.NET textbox input value into upcase right way?

Add following javascript into ASP.NET textbox control

How to add ajax validation on field in ASP.NET MVC 3?
By Remote Attribute. This way is MS designed for you.

//In Model
        [Remote("CheckExistedEmail", "ControllerName")]
        [Required]
        [DataType(DataType.EmailAddress)]
        [Display(Name = "Email address")]
        [RegularExpression(@"^[_a-z0-9-]+(\.[_a-z0-9-]+)*@[a-z0-9-]+(\.[a-z0-9-]+)*(\.[a-z]{2,4})$",ErrorMessage="Invalid email address")]
        public string Email { get; set; }

//In Action 
        public JsonResult CheckExistedEmail(string Email)
        {
            if (EmailExisted(Email))
            {
                return Json("Existed Email.", JsonRequestBehavior.AllowGet);
            }
            else
            {
                return Json(true, JsonRequestBehavior.AllowGet);
            }
        }

http://msdn.microsoft.com/en-us/library/gg453903(v=vs.98).aspx

How many ways to redirect URL in Javascript?

1. window.location.href=”login.htm";
2. window.navigate(”login.htm”);
3. self.location=”login.htm”;

Any other way?

How to disable browser back button in asp.net?

Should make ASP.NET page cache expired instead of disable browser back button

Page.Response.Cache.SetCacheability(HttpCacheability.NoCache)

How to get active users in last 10 minutes in ASP.NET membership database?

select top 300 * from dbo.aspnet_Users u
where u.LastActivityDate > DATEADD(minute, -10, GETUTCDATE())
order by u.LastActivityDate desc

How to fix problem: missing files when publish a website in Visual Studio for ASP.NET?

In Visual Studiio, Content files need to be marked for publishing
Right click on the file missed -> Properties -> Build Action set to Content.

How to find common items in two set of items in C#?

            var list1 = new List() { 1, 3, 4, 5 };
            var list2 = new List() { 2, 3, 4, 5 };
            var commonItems = list1.Intersect(list2);

OAuth with ASP.NET MVC and WorldDomination.Web.Authentication

http://www.philliphaydon.com/2013/02/oauth-with-asp-net-mvc-and-world-domination-authentication/

MVC 4: facebook twitter login with oAuth

http://www.dotnetexpertguide.com/2012/08/facebook-twitter-oauth-openid-login-with-aspnet-mvc-4-application.html

How to set Connection: Keep-Alive in C# HttpWebRequest class ?

Cannot set by: webrequest.KeepAlive = true;
Have to set this request header by reflection

var req = (HttpWebRequest)WebRequest.Create(someUrl);

var sp = req.ServicePoint;
var prop = sp.GetType().GetProperty("HttpBehaviour", BindingFlags.Instance | BindingFlags.NonPublic);
prop.SetValue(sp, (byte)0, null);

Reference:
http://stackoverflow.com/questions/7458556/c-sharp-connection-keep-alive-header-is-not-being-sent-during-httpwebrequest

How to validate a URL in ASP.NET?

By Regular expression data annotation in Model class

[RegularExpression(@"^(http|https|ftp)\://([a-zA-Z0-9\.\-]+(\:[a-zA-Z0-9\.&%\$\-]+)*@)*((25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[1-9])\.(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[1-9]|0)\.(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[1-9]|0)\.(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[0-9])|localhost|([a-zA-Z0-9\-]+\.)*[a-zA-Z0-9\-]+\.(com|edu|gov|int|mil|net|org|biz|arpa|info|name|pro|aero|coop|museum|[a-zA-Z]{2}))(\:[0-9]+)*(/($|[a-zA-Z0-9\.\,\?\'\\\+&%\$#\=~_\-]+))*$", ErrorMessage = "Invalid url")]
public string Url { get; set; }

How to set Max length for an input in ASP.NET MVC

By StringLength data annotation

[StringLength(20, ErrorMessage = "Name cannot be longer than 20 characters.")]
public string Name { get; set; }

How to use TextArea for @Html.EditorFor in ASP.NET MVC?

Two ways:
1. Add data annotation in Model class
[DataType(DataType.MultilineText)]
public string Text { get; set; }

2. @Html.TextAreaFor(model => model.Text)

How to change EditFor width in ASP.NET MVC 3?

Should be very simple? But need to two steps to do so:
1. Replace EditFor with TextBoxFor
2. Pass html property into TextBoxFor

@Html.TextBoxFor(m => m.Name, new {style = "width:50px"})

How to add data annotations to a class without changing it?

By MetadataType class
- Inherent from it, make it to be base class
- Then use metadata class to add validation data annotations in subclass

[MetadataType(typeof(ModelMetadata))]
public class Model : Base_Class {
}


internal class ModelMetadata {
    [Required]
    public string Name { get; set; }
}