c# - Convert string to nullable type (int, double, etc...) - Stack Overflow

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Mon Sep 25 2023 12:54:55 GMT+0000 (Coordinated Universal Time)

Saved by @rick_m #c#

public static Nullable<T> ToNullable<T>(this string s) where T: struct
{
    Nullable<T> result = new Nullable<T>();
    try
    {
        if (!string.IsNullOrEmpty(s) && s.Trim().Length > 0)
        {
            TypeConverter conv = TypeDescriptor.GetConverter(typeof(T));
            result = (T)conv.ConvertFrom(s);
        }
    }
    catch { } 
    return result;
}

https://stackoverflow.com/questions/773078/convert-string-to-nullable-type-int-double-etc

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C#

@rick_m

c.ParseArray c.StringExtensions.ReplaceAll c.StringExtensions.ReplaceFirstInstance c.StringExtensions.ReplaceFirstInstance c.StringExtensions.ToShortDescription c.StringExtensions.StripSpecialCharacters c.StringExtensions.StripExtraSpaces c.StringExtension.Left j.Kendo.GridFilter c.CacheHelper c.DateRangeHelper c.EnumerableComparer c.NaturalSort c.IsPlural c.Pluralize c.Singularize c.IsSingular c.Abbreviate c.Retry c.FullyQualifiedApplicationPath c.FullyQualifiedHostWebAddress c.IsDivisible c.CompareListAndDataTable c.DataTableRowsNotInList c.ConvertCommaDelimmitedStringOfIntegersToArrayOfInts c.GetLastInstanceOf c.StringExtensions.ToNullableDateTime c.Excel.CloneWorksheet c.FindItemsNotInSmallerStringArray c# - Convert string to nullable type (int, double, etc...) - Stack Overflow C# Timespan.ToFriendlyDisplay

#blazor #c# #html

[SOLVED] - Blazor onchange event with select dropdown

@inject HttpClient httpClient

@if (States != null)
{

<select id="SearchStateId" name="stateId" @onchange="DoStuff" class="form-control1">
    <option>@InitialText</option>
    @foreach (var state in States)
    {
        <option value="@state.Name">@state.Name</option>
    }
</select>
}


@code {
[Parameter] public string InitialText { get; set; } = "Select State";
private KeyValue[] States;
private string selectedString { get; set; }
protected override async Task OnInitializedAsync()
{
    States = await httpClient.GetJsonAsync<KeyValue[]>("/sample-data/State.json");
}

private void DoStuff(ChangeEventArgs e)
{
    selectedString = e.Value.ToString();
    Console.WriteLine("It is definitely: " + selectedString);
}

public class KeyValue
{
    public int Id { get; set; }

    public string Name { get; set; }
}
}

Unity Convert LocalSpace to WorldSpace

//You need this because ur velocity is in localSpace
//This works if you start the game at 0,0,0 rotation,
//what if you start the game at 0,180,0 rotation?  
//Then your up arrow will move you backwards.


//Get inputs
float horzInput = Input.GetAxis("Horizontal");
float vertInput = Input.GetAxis("Vertical");

//Calc Velocity
Vector3 direction = new Vector3(horzInput, 0.0f, vertInput);
Vector3 velocity = direction * _speed;

//Gravity
velocity.y -= _gravity;

//Convert localSpace velocity to worldSpace
velocity = transform.transform.TransformDirection(velocity); //<-Weimberger's way
velocity = transform.TransformDirection(velocity); //<-myWay

//Move
_controller.Move(velocity * Time.deltaTime);

Unity (C#) equivalent of SetInterval()

void Start(){ 
  StartCoroutine(SpawnObject()); 
}

IEnumerator SpawnObject(){
  while (true){
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I want Input text file in sap using c#

   foreach (string line in lines)
            {
                string[] a = line.Split('|');
                oDocumentSQ.DocNum = Convert.ToInt32(a[0]);
                oDocumentSQ.CardCode = a[1];
                oDocumentSQ.NumAtCard = a[2];
                oDocumentSQ.DocDate = Convert.ToDateTime(a[3]);

                oDocumentSQ.Lines.ItemCode = a[4];
                oDocumentSQ.Lines.UnitPrice = Convert.ToDouble(a[5]);
                oDocumentSQ.Lines.Quantity = Convert.ToInt32(a[6]);
                oDocumentSQ.Lines.VatGroup = a[7];
                oDocumentSQ.Lines.Add();             
            }

#C# #c# #array #dictionary

How to clear item not input when count frequency use Dictionary C#

for (int i = 0; i < n; i++)
{
    if (valCount.ContainsKey(x))
        valCount[x]++;
    else
        valCount[x] = 1;
}

NuGet Gallery | DocumentFormat.OpenXml 2.11.0

Install-Package DocumentFormat.OpenXml -Version 2.11.0

How to initialize a dictionary with a collection initializer - C# Programming Guide | Microsoft Docs

public class HowToDictionaryInitializer
{
    class StudentName
    {
        public string FirstName { get; set; }
        public string LastName { get; set; }
        public int ID { get; set; }
    }

    public static void Main()
    {
        var students = new Dictionary<int, StudentName>()
        {
            { 111, new StudentName { FirstName="Sachin", LastName="Karnik", ID=211 } },
            { 112, new StudentName { FirstName="Dina", LastName="Salimzianova", ID=317 } },
            { 113, new StudentName { FirstName="Andy", LastName="Ruth", ID=198 } }
        };

        foreach(var index in Enumerable.Range(111, 3))
        {
            Console.WriteLine($"Student {index} is {students[index].FirstName} {students[index].LastName}");
        }
        Console.WriteLine();		

        var students2 = new Dictionary<int, StudentName>()
        {
            [111] = new StudentName { FirstName="Sachin", LastName="Karnik", ID=211 },
            [112] = new StudentName { FirstName="Dina", LastName="Salimzianova", ID=317 } ,
            [113] = new StudentName { FirstName="Andy", LastName="Ruth", ID=198 }
        };

        foreach (var index in Enumerable.Range(111, 3))
        {
            Console.WriteLine($"Student {index} is {students2[index].FirstName} {students2[index].LastName}");
        }
    }
}

public int Id { get; set; }

        [Required]
        public string Klant { get; set; }

        [DataType(DataType.EmailAddress)]
        public string Email { get; set; }

        [DataType(DataType.PhoneNumber)]
        public string Telefoonnummer { get; set; }

        [Required]
        public int Aantalpersonen { get; set; }

        [Required]
        [DataType(DataType.Date)]
        public DateTime Datum { get; set; }

        [Required]
        [DataType(DataType.Time)]
        public DateTime Begintijd { get; set; }

        [Required]
        [DataType(DataType.Time)]
        public DateTime Eindtijd { get; set; }

        [DataType(DataType.MultilineText)]
        public string Opmerkingen { get; set; }
        public string Medewerker { get; set; }
        public DateTime AanmaakDatum { get; set; }

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;

namespace GoodTimes.Models
{
    public class Bon
    {
        public int Id { get; set; }
        public int Tafelnr { get; set; }
        public DateTime Bezoek { get; set; }
        public string Medewerker { get; set; }
        public int Bonnummer { get; set; }

        public List<BonRegel> BonRegels { get; set; }

        public List<Bestelling> Bestellings { get; set; }
    }
}

Class Reserveren

using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.Threading.Tasks;

namespace GoodTimes.Models
{
    public class Reserveren
    {
        public int Id { get; set; }

        [Required]
        public string Klant { get; set; }

        [DataType(DataType.EmailAddress)]
        public string Email { get; set; }

        [DataType(DataType.PhoneNumber)]
        public string Telefoonnummer { get; set; }

        [Required]
        public int Aantalpersonen { get; set; }

        [Required]
        [DataType(DataType.Date)]
        public DateTime Datum { get; set; }

        [Required]
        [DataType(DataType.Time)]
        public DateTime Begintijd { get; set; }

        [Required]
        [DataType(DataType.Time)]
        public DateTime Eindtijd { get; set; }

        [DataType(DataType.MultilineText)]
        public string Opmerkingen { get; set; }
        public string Medewerker { get; set; }
        public DateTime AanmaakDatum { get; set; }
    }
}

ApplicationDbContext

using System;
using System.Collections.Generic;
using System.Text;
using Microsoft.AspNetCore.Identity.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore;
using GoodTimes.Models;

namespace GoodTimes.Data
{
    public class ApplicationDbContext : IdentityDbContext
    {
        public ApplicationDbContext(DbContextOptions<ApplicationDbContext> options)
            : base(options)
        {
        }
        public DbSet<GoodTimes.Models.Reserveren> Reserveren { get; set; }
        public DbSet<GoodTimes.Models.Menukaart> Menukaart { get; set; }
        public DbSet<GoodTimes.Models.Categorie> Categorie { get; set; }
        public DbSet<GoodTimes.Models.Product> Product { get; set; }

        protected override void OnModelCreating(ModelBuilder builder)
        {
            base.OnModelCreating(builder);
            builder.Entity<Menukaart>().HasData(
                new Menukaart
                {
                    Id = 1,
                    Naam = "Lunchkaart"
                },
                new Menukaart
                {
                    Id = 2,
                    Naam = "Dinerkaart"
                },
                new Menukaart
                {
                    Id = 3,
                    Naam = "Drankenkaart"
                }
            );
        }

        public DbSet<GoodTimes.Models.Bestelling> Bestelling { get; set; }

        //public DbSet<GoodTimes.Models.Bon> Bon { get; set; }

        //public DbSet<GoodTimes.Models.BonRegel> BonRegel { get; set; }
    }
}

using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.Threading.Tasks;

namespace GoodTimes.Models
{
    public class Bestelling
    {
        public int Id { get; set; }
        public int Tafelnummer { get; set; }
        public int Aantal { get; set; }
        [DataType(DataType.MultilineText)]
        public string Opmerkingen { get; set; }
        public string Medewerker { get; set; }
        public DateTime Plaatsing { get; set; }
        public bool IsGereed { get; set; }

        //public List<BonRegel> BonRegels { get; set; }

        //public int BonId { get; set; }
        //public Bon Bon { get; set; }
    }
}

using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.Threading.Tasks;

namespace GoodTimes.Models
{
    public class Categorie
    {
        public int Id { get; set; }
        [Required]
        public string Naam { get; set; }
        public int Volgorde { get; set; }

        public int MenukaartId { get; set; }
        public Menukaart Menukaart { get; set; }

        public List<Product> products { get; set; }
    }
}

using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.Threading.Tasks;

namespace GoodTimes.Models
{
    public class Product
    {
        public int Id { get; set; }
        [Required]
        public string Naam { get; set; }
        [Required]
        [DataType(DataType.MultilineText)]
        public string Omschrijving { get; set; }
        [Required]
        public double Prijs { get; set; }
        public int Volgorde { get; set; }

        public int CategorieId { get; set; }
        public Categorie categorie { get; set; }
    }
}

#c# #loops #for

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace StarPattern
{
class Program
{
static void Main(string[] args)
{
int x, y, z;
for (x =6; x >= 1; x--)
{
for (y = 1; y < x; y++)
{
Console.Write(" ");
}
for (z = 6; z >= x; z--)
{
Console.Write("*");
}
Console.WriteLine();
}
Console.ReadLine();
}
}
}

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