How to do - MS SQL C# Excel Access

MVC - Display Nullable checkbox

2022-07-15T12:07:00.005-07:00

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Replace

@Html.CheckBoxFor(x => x.MyQuestions)

with

@Html.CheckBox("MyQuestions", Model.MyQuestions ?? false)

MVC - Custom Validate Checkbox - Get checkbox value in JavaScript (client)

2022-07-15T11:57:00.004-07:00

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1. Validation

public IEnumerable<ModelClientValidationRule> GetClientValidationRules(ModelMetadata metadata, ControllerContext context)

{

var rule = new ModelClientValidationRule

{

ValidationType = "validatecheckbox",

ErrorMessage = "Fix it!"

};

rule.ValidationParameters.Add("fields", string.Join(",", _fields));

yield return rule;

}

2. JS

$.validator.addMethod('validatecheckbox', function (value, element, params) {

debugger

var isValid = true;

if ($(params)[0].fields[1].val() == "True"){

if ($(params)[0].fields[0][0].checked == false) {

isValid = false;

}

});

MVC - How to make a read only checkbox

2022-07-13T13:21:00.008-07:00

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Replace

@model WebApplication3.Models.EmployeeList

@using (Html.BeginForm(null, null, FormMethod.Post))

{

if (Model.myEmployees != null)

{

foreach (var item in Model.myEmployees)

{

@Html.CheckBoxFor(modelItem => item.IsValid.Value, new { id = item.EmployeeID})

@Html.DisplayFor(modelItem => item.FirstName)

<br />

}

with

@model WebApplication3.Models.EmployeeList

@using (Html.BeginForm(null, null, FormMethod.Post))

{

if (Model.myEmployees != null)

{

foreach (var item in Model.myEmployees)

{

@Html.CheckBoxFor(modelItem => item.IsValid.Value, new { id = item.EmployeeID, @disabled = "true"})

@Html.DisplayFor(modelItem => item.FirstName)

<br />

}

MVC - Fix Error - CS0428: Cannot convert method group 'GetValueOrDefault' to non-delegate type 'bool'. Did you intend to invoke the method?

2022-07-13T12:01:00.008-07:00

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To fix it replace

@model WebApplication3.Models.EmployeeList

@using (Html.BeginForm(null, null, FormMethod.Post))

{

if (Model.myEmployees != null)

{

foreach (var item in Model.myEmployees)

{

@Html.CheckBoxFor(modelItem => item.IsValid.GetValueOrDefault, new { id = item.EmployeeID })

@Html.DisplayFor(modelItem => item.FirstName)

}

with

@model WebApplication3.Models.EmployeeList

@using (Html.BeginForm(null, null, FormMethod.Post))

{

if (Model.myEmployees != null)

{

foreach (var item in Model.myEmployees)

{

@Html.CheckBoxFor(modelItem => item.IsValid.Value, new { id = item.EmployeeID })

@Html.DisplayFor(modelItem => item.FirstName)

}

Fix Error CS0266 Cannot implicitly convert type 'bool?' to 'bool'. An explicit conversion exists (are you missing a cast?)

2022-07-13T11:42:00.005-07:00

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to fix it replace

@model WebApplication3.Models.EmployeeList

@using (Html.BeginForm(null, null, FormMethod.Post))

{

if (Model.myEmployees != null)

{

foreach (var item in Model.myEmployees)

{

@Html.CheckBoxFor(modelItem => item.IsValid, new { id = item.EmployeeID })

@Html.DisplayFor(modelItem => item.FirstName)

}

with

@model WebApplication3.Models.EmployeeList

@using (Html.BeginForm(null, null, FormMethod.Post))

{

if (Model.myEmployees != null)

{

foreach (var item in Model.myEmployees)

{

@Html.CheckBoxFor(modelItem => item.IsValid.Value, new { id = item.EmployeeID })

@Html.DisplayFor(modelItem => item.FirstName)

}

CS0119 'Employee List' is a type, which is not valid in the given context

2022-07-13T11:11:00.008-07:00

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To fix this error replace (semicolon) in view

@model WebApplication3.Models.EmployeeList;

with

@model WebApplication3.Models.EmployeeList

MSSQL - Check if varchar contains specified characteer

2022-07-12T12:27:00.004-07:00

Declare @Test varchar(100) = 'aaa@aaa';

IF @Test Like '%@%'

BEGIN

print ' contains @'

END

ELSE

BEGIN

print ' doesn''t contain @'

END

MSSQL - How to increase length of existing varchar

2021-04-06T14:12:00.004-07:00

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ALter Table Test01
Alter Column RealName Varchar(100)

MSSQL - Rename column in table

2021-04-06T14:09:00.004-07:00

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exec sp_rename 'TableName.CurrentColumnName', 'NewColumnName', 'COLUMN'

MSSQL - Rename table

2021-04-06T14:07:00.002-07:00

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exec sp_rename 'CurrentTableName' , 'NewTableName'

MSSQL - Fix Error - Column names in each table must be unique. Column name 'IsValid' in table 'Test1' is specified more than once.

2021-04-05T14:37:00.002-07:00

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To fix it replace

Alter Table Test1
Add IsValid bit not null Default 0

with

IF COL_LENGTH('dbo.Test1', 'IsValid') Is Null
Begin
Alter Table Test1
Add IsValid bit not null Default 0
End

MSSQL - Add column only if it doesn't exist

2021-04-05T14:34:00.003-07:00

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IF COL_LENGTH('dbo.Test3', 'IsValid') is null
Begin
Alter Table Test3 Add IsValid bit not null default 0
End

Select * from Test3

MSSQL - Fix Error - ALTER TABLE only allows columns to be added that can contain nulls, or have a DEFAULT definition specified, or the column being added is an identity or timestamp column, or alternatively if none of the previous conditions are satisfied the table must be empty to allow addition of this column. Column 'IsValid' cannot be added to non-empty table 'Test1' because it does not satisfy these conditions.

2021-04-05T14:30:00.002-07:00

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To fix it replace

Alter Table Test1
Add IsValid bit not null

with

Alter Table Test1
Add IsValid bit not null Default 0

MVC5 - Add modal (popup dialog)

2021-04-01T14:03:00.004-07:00

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1. View

@{
    ViewBag.Title = "Home Page";
}
<div class="AddPopUp">
    @Html.Label("Add pop up")
</div>
<div class="modal fade" id="MyPopUp" role="dialog">
    <div class="modal-dialog">
        <div class="modal-content">
            <div class="modal-body">
                here are going your controls etc
            </div>
        </div>
    </div>
</div>

@section Scripts{
    <script type="text/javascript">
        $(document).ready(function () {
            $(".AddPopUp").click(function (e) {
                $('#MyPopUp').modal('show');
            });
        });
    </script>
    }

2. CSS

.modal-content{
height: 500px;
width: 700px;
}

MVC - Simplest Extension Method example

2021-03-19T14:18:00.004-07:00

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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

2021-03-19T14:14:00.006-07:00

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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

2021-03-19T14:11:00.004-07:00

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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)

2021-03-19T14:08:00.003-07:00

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

MVC - C# - Convert Now to Universal Time UTC

2021-03-19T14:05:00.003-07:00

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

MVC - C# - Format Date

2021-03-19T14:02:00.003-07:00

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MVC - C# - Format Date

Bat file to execute PowerShell

2021-03-18T13:58:00.001-07:00

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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

2021-03-17T14:12:00.004-07:00

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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.

2021-03-17T14:09:00.003-07:00

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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

2021-03-17T14:00:00.004-07:00

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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

2021-03-16T14:00:00.003-07:00

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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();
        }