MVC - Simplest Extension Method example

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 1. Model

   public interface IExtensionTest
    {
         void DoSomething();
    }
    public class ExtensionTest: IExtensionTest
    {
        public void DoSomething() { }
    }
    public static class SomethingElse {
        public static string ReturnSomething(this IExtensionTest t, string s)
        {
            return "returning: " + s;
        }
    }

2. Controller

        public ActionResult Index()
        {
            IExtensionTest e = new ExtensionTest();
            var res = e.ReturnSomething("bbbbb");
            return View();
        }

MVC - C# - Check if DateTime is today

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            DateTime d = Convert.ToDateTime("1/1/2000");
            if (d != DateTime.Today)
            {
                // do something here.
            }

MVC - C# - Check if time is greater than something

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            TimeSpan startSomething = new TimeSpan(8, 0, 0);
            TimeSpan endSomething = new TimeSpan(16, 0, 0);
            TimeSpan now = DateTime.Now.TimeOfDay;
            if ((now > startSomething) && (now < endSomething))
            {
                //do something here
            } 

MVC - C# - Check if today is Friday (check todays day name)

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         if (System.DateTime.Now.DayOfWeek == DayOfWeek.Friday)
            {
                // do somehting here
            }

MVC - C# - Convert Now to Universal Time UTC

 

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           String t = Convert.ToDateTime(DateTime.Now).ToUniversalTime().ToString("yyyy/MM/dd HH:mm UTC");
 

 

MVC - C# - Format Date

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MVC - C# - Format Date

Bat file to execute PowerShell

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 1. PowerShell File

$wshell = New-Object -ComObject Wscript.Shell
$wshell.Popup("Hello World", 0, "Done", 0x1)

2. Bat file

Powershell.exe -executionpolicy remotesigned -File "C:\Temp\PopupTest.ps1"

MVC - How to call async method from controller

 

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1. Task

using System.Web.Mvc;
using System.Threading.Tasks;

namespace ValidateOnDbSide.Controllers
{
    public class BusinessController : Controller
    {
        public async Task<string> DoSomething()
        {
           return await Task.Run(() => test());
        }
        public string test()
        {
            return "test";
        }        
    }
}

2. Controller

using System.Threading.Tasks;

namespace ValidateOnDbSide.Controllers
{
    public class HomeController : Controller
    {
        CompanyEntities db = new CompanyEntities();

       

        public async Task<ActionResult> Index()
        {
            BusinessController b = new BusinessController();
            //Task c = b.DoSomething();
            string res = await b.DoSomething();

            return View();
        }

MVC - Fix Error - Because this call is not awaited, execution of the current method continues before the call is completed. Consider applying the 'await' operator to the result of the call.

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 Because this call is not awaited, execution of the current method continues before the call is completed. Consider applying the 'await' operator to the result of the call.   

To fix it replace

        public ActionResult Index()
        {
            BusinessController b = new BusinessController();
            b.DoSomething();

            return View();
        }

with

using System.Threading.Tasks;

        public async Task< ActionResult> Index()
        {
            BusinessController b = new BusinessController();
            await b.DoSomething();

            return View();
        }

MVC - Add scrollbar to @Html.DisplayFor

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1.CSS

 .LongText{
    word-wrap:break-word;
    height: 10em;
    width: 20em;
    overflow-y: scroll;
}

2.View 

    <div class="LongText">
        @Html.DisplayFor(x => x.Description)
    </div>

MVC - Prevent Double clicking

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1. View

@{
    ViewBag.Title = "Home Page";
}
<input type="submit" value="SUBMIT" />
<input type="submit" value="CANCEL" />

@section Scripts{
    <script type="text/javascript">

    $(document).ready(function () {
        var clickNum = 0;
        jQuery('input[type=submit]').click(function (event) {
            if (this.value == 'CANCEL') {
                clickNum = 0;
                return false;
            }
            if (clickNum > 0) {
                alert("Wait!!!!!");
                return false;
            }
            else {
                clickNum++;
            }
        });


    });
</script>
}
 

2. Controller

        public ActionResult Index()
        {
            return View();
        }

        [HttpPost]
        public ActionResult Index(string test = "")
        {
            System.Timers.Timer t = new System.Timers.Timer(2000);
            return View();
        }

 

MVC - Create simple WebApiConfig

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1. Install NuGet

PM> Install-Package Microsoft.AspNet.WebApi.WebHost

PM> Install-Package Microsoft.AspNet.WebApi

2. Add to App_Start folder

using System.Web.Http;

namespace WebApplication17
{
    public static class WebAppConfig
    {
        public static void Register(HttpConfiguration config)
        {
            config.Routes.MapHttpRoute("API Default", "api/{controller}/{id}",
                new { id = RouteParameter.Optional });
        }
    }
}

3. Modify Global.asax

using System.Web.Mvc;
using System.Web.Optimization;
using System.Web.Routing;
using System.Web.Http;

namespace WebApplication17
{
    public class MvcApplication : System.Web.HttpApplication
    {
        protected void Application_Start()
        {
            AreaRegistration.RegisterAllAreas();
            FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);
            WebAppConfig.Register(GlobalConfiguration.Configuration);
            RouteConfig.RegisterRoutes(RouteTable.Routes);
            BundleConfig.RegisterBundles(BundleTable.Bundles);
        }
    }
}

4. Modify Layout file

    @Styles.Render("~/Content/css")
    @Scripts.Render("~/bundles/modernizr")
    @Scripts.Render("~/Scripts/jquery-1.10.2.min.js")
</head>

5. Create empty controller

namespace WebApplication17.Controllers
{
    public class TestController : System.Web.Http.ApiController
    {
        public string Get()
        {
            return "returning something";
        }
    }
}

6. Modify Home\Index file

@{
    ViewBag.Title = "Home Page";
}
<script>
    var url = '/api/test';
    $(document).ready(function () {
        $.ajax({
            url: url,
            async: true,
            success: function (data) {
                alert(data);
            }
        });
    });
</script>

MVC - Fix error - JavaScript runtime error: '$' is undefined

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To fix it replace layout file

    @Styles.Render("~/Content/css")
    @Scripts.Render("~/bundles/modernizr")
</head>

with 

    @Styles.Render("~/Content/css")
    @Scripts.Render("~/bundles/modernizr")
    @Scripts.Render("~/Scripts/jquery-1.10.2.min.js")
</head>

MVC - WebApiConfing - Controller not called - Fix Error - The resource cannot be found

 

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1. View - add error

<script>
    var uri = '/api/test';
    $(document).ready(function () {

        $.ajax({
            url: 'api/test',
            async: true,
            success: function(data){
                alert(data);
            },
            error: function (xhr, status, error) {
                debugger
            }
        });
      
    });
</script> 

2. Global replace

        protected void Application_Start()
        {
            AreaRegistration.RegisterAllAreas();
            FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters); 
            RouteConfig.RegisterRoutes(RouteTable.Routes);
            BundleConfig.RegisterBundles(BundleTable.Bundles);
            WebApiConfig.Register(GlobalConfiguration.Configuration);
        }

with 

        protected void Application_Start()
        {
            AreaRegistration.RegisterAllAreas();
            FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);
            WebApiConfig.Register(GlobalConfiguration.Configuration);
            RouteConfig.RegisterRoutes(RouteTable.Routes);
            BundleConfig.RegisterBundles(BundleTable.Bundles);
           
        }

 

MVC - WebApiConfing - Fix Error - The requested resource does not support http method 'GET'

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 to fix it add to the controller

        [System.Web.Http.AcceptVerbs("GET", "POST")]
        [System.Web.Http.HttpGet]

so it looks like

using System.Web.Mvc;

namespace WebApplication11.Controllers
{
    [RoutePrefix("api/Device")]
    public class TestController : System.Web.Http.ApiController
    {
        [System.Web.Http.AcceptVerbs("GET", "POST")]
        [System.Web.Http.HttpGet]
        public string f1()
        {
            return "hello world";
        }
        public string f1(int a)
        {
            return (a + 1).ToString();
        }
    }
}

MVC - C# - Check if valid email address

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       public ActionResult Index()
        {
            var b1 = IsValidEmailAddress("bob@boc.com");
            var b2 = IsValidEmailAddress("Bob@bob@bob");
            return View();
        }

        private bool IsValidEmailAddress(string email)
        {
            try
            {
                var addr = new System.Net.Mail.MailAddress(email);
                return addr.Address == email;
            }
            catch
            {
                return false;
            }
        }

MVC - Remote Validation - Passing multiple additional fiels for validation

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Replace

   [Remote(action: "ValidateSalary", controller: "Home",  ErrorMessage ="will never be displayed - it will display message returned by stored procedure")]
        public int Salary { get; set; }

with

  [Remote(action: "ValidateSalary", controller: "Home", AdditionalFields = "FirstName,LastName",  ErrorMessage ="will never be displayed - it will display message returned by stored procedure")]
        public int Salary { get; set; }

MVC - Validation - Allow all characters except specified ones

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 [RegularExpression (@"^[^*<>a]*$", ErrorMessage = " invalid")]
        public string LastName { get; set; }

MVC - Validation - Display proper name in error message

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  [RegularExpression(@"^([0-9]\d*)(?:\.[05]0?)?$", ErrorMessage = " {0} contains invalid characters")]
        [Display(Name = "Salary abc...")]
        public Decimal Salary { get; set; }

MVC - Validation - Allow half deciamals - 0.5

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        [RegularExpression(@"^([0-9]\d*)(?:\.[05]0?)?$", ErrorMessage = " {0} contains invalid characters")]
        public Decimal Salary { get; set; }

MVC - Custom Validator - Fix Error - 0x800a138f - JavaScript runtime error: Unable to get property 'unobtrusive' of undefined or null reference

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 0x800a138f - JavaScript runtime error: Unable to get property 'unobtrusive' of undefined or null reference

 

 

In Layout replace

 

 

    @Scripts.Render("~/bundles/jqueryval")

    @Scripts.Render("~/bundles/jquery")
    @Scripts.Render("~/Scripts/CustomValidation.js")
    @Scripts.Render("~/bundles/bootstrap")
    @RenderSection("scripts", required: false)
</body>
</html>

 

with

 
    @Scripts.Render("~/bundles/jquery")
    @Scripts.Render("~/bundles/jqueryval")
    @Scripts.Render("~/Scripts/CustomValidation.js")
    @Scripts.Render("~/bundles/bootstrap")
    @RenderSection("scripts", required: false)
</body>
</html>

MVC - Custom Validation - Validate on each checkbox click

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@model WebApplication10.Models.Customer

@{ Html.EnableClientValidation();}
@using(Html.BeginForm(null, null, FormMethod.Post))
{
    @Html.AntiForgeryToken();
    @Html.CheckBoxFor(x => x.IsActive)
    @Html.TextBoxFor(x => x.FirstName)
    @Html.ValidationMessageFor(x => x.FirstName)

    @Html.TextBoxFor(x => x.LastName)

    <input type="submit" value="SUBMIT" />
}

@section Scripts{
    <script type="text/javascript">
        $("#IsActive").change(function (evt) {
            var validator = $("#FirstName").validate();
            var IsValid = $("#FirstName").valid();
        });
    </script>
}

MVC - Remote Validation - Button not included in POST data in Controller

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 Button value lost in Remote Validator

 

to fix it replace

 @model ValidateOnDbSide.Models.Customer


@{ Html.EnableClientValidation();}
@using (Html.BeginForm(null, null, FormMethod.Post, new { id = "UserID" }))
{

    @Html.AntiForgeryToken()

    // @Html.CheckBoxFor(x => x.IsActive)
    @Html.DisplayNameFor(x => x.FirstName)
    @Html.TextBoxFor(x => x.FirstName)
    @Html.ValidationMessageFor(x => x.FirstName)
    <br />
    @Html.DisplayNameFor(x => x.LastName)
    @Html.TextBoxFor(x => x.LastName)
    @Html.ValidationMessageFor(x => x.LastName)
    <br />

     @Html.DisplayNameFor(x => x.Salary)
    @Html.TextBoxFor(x => x.Salary)
    @Html.ValidationMessageFor(x => x.Salary)
    <br />
    <input type="submit" value="Submit" name="btn" />
}

with 

@model ValidateOnDbSide.Models.Customer


@{ Html.EnableClientValidation();}
@using (Html.BeginForm(null, null, FormMethod.Post, new { id = "UserID" }))
{

    @Html.AntiForgeryToken()

    // @Html.CheckBoxFor(x => x.IsActive)
    @Html.DisplayNameFor(x => x.FirstName)
    @Html.TextBoxFor(x => x.FirstName)
    @Html.ValidationMessageFor(x => x.FirstName)
    <br />
    @Html.DisplayNameFor(x => x.LastName)
    @Html.TextBoxFor(x => x.LastName)
    @Html.ValidationMessageFor(x => x.LastName)
    <br />

     @Html.DisplayNameFor(x => x.Salary)
    @Html.TextBoxFor(x => x.Salary)
    @Html.ValidationMessageFor(x => x.Salary)
    <br />
    <input type="submit" value="Submit" name="btn" />
}

@section Scripts{
    <script type="text/javascript">
        $(document).ready(function () {
            $('input[type="submit"]').click(function () {
                var hidden = $("<input type='hidden' />").attr("name", this.name).val(this.value).appendTo($(this).closest("form"));
            });
        });
    </script>    
    
}