C#•16mo ago

❔ problem with DateTime format

guys, the "[DisplayFormat(DataFormatString = "{dd/MM/yyyy}")]" is not working for me: when i add an event or update it, still shows like this { "title": "string", "description": "string", "date": "2023-08-28T22:43:42.452Z", "attendees": [ "string" ] } can somebody help me?

using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;
using System.Net;
using System.Text.Json.Serialization;
using Microsoft.AspNetCore.Identity;



namespace EventEnroll.Models
{
    public class Event
    {
        [Key]
        public int EventId { get; set; }
        [Required]
        [MinLength(8, ErrorMessage = "Title must be at least 8 characters.")]
        public string Title { get; set; } = string.Empty;

        [MaxLength(50, ErrorMessage = "Description cannot exceed 50 characters.")]
        public string Description { get; set; } = string.Empty;

        [Required]
        [DisplayFormat(DataFormatString = "{dd/MM/yyyy}")]
        public DateTime Date { get; set; }
        public string? CreatorId { get; set; }
        [ForeignKey("CreatorId")]
        public IdentityUser? Creator { get; set; }
        // Navigation properties
        public ICollection<IdentityUser>? Attendees { get; set; } = new List<IdentityUser>();

    }
}

using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;
using System.Net;
using System.Text.Json.Serialization;
using Microsoft.AspNetCore.Identity;



namespace EventEnroll.Models
{
    public class Event
    {
        [Key]
        public int EventId { get; set; }
        [Required]
        [MinLength(8, ErrorMessage = "Title must be at least 8 characters.")]
        public string Title { get; set; } = string.Empty;

        [MaxLength(50, ErrorMessage = "Description cannot exceed 50 characters.")]
        public string Description { get; set; } = string.Empty;

        [Required]
        [DisplayFormat(DataFormatString = "{dd/MM/yyyy}")]
        public DateTime Date { get; set; }
        public string? CreatorId { get; set; }
        [ForeignKey("CreatorId")]
        public IdentityUser? Creator { get; set; }
        // Navigation properties
        public ICollection<IdentityUser>? Attendees { get; set; } = new List<IdentityUser>();

    }
}

20 Replies

Angius•16mo ago

Database entities should never be concerned with how they're represented. I'd even argue, they should not be represented period, but rather selected into a DTO Also, it's possible that this attribute simply doesn't work with JSON serialization I'd say, the date should be sent as ISO8601 like it happens now, and it should be the concern of the frontend to display it in whatever format is desired

PedroOP•16mo ago

i tried that

using EventEnroll.Models;
using Microsoft.AspNetCore.Identity;
using System.ComponentModel.DataAnnotations;
using System.Text.Json.Serialization;

namespace EventEnroll.Dtos.Event
{
    public class AddEventDto
    {

        public string Title { get; set; } = string.Empty;
        public string Description { get; set; } = string.Empty;
        [DisplayFormat(DataFormatString = "{0:dd/MM/yyyy}")]
        public DateTime Date { get; set; }
        [JsonIgnore]
        public string? CreatorId { get; set; }
        [Required]
        public List<string> Attendees { get; set; } = new List<string>();

    }
}

using EventEnroll.Models;
using Microsoft.AspNetCore.Identity;
using System.ComponentModel.DataAnnotations;
using System.Text.Json.Serialization;

namespace EventEnroll.Dtos.Event
{
    public class AddEventDto
    {

        public string Title { get; set; } = string.Empty;
        public string Description { get; set; } = string.Empty;
        [DisplayFormat(DataFormatString = "{0:dd/MM/yyyy}")]
        public DateTime Date { get; set; }
        [JsonIgnore]
        public string? CreatorId { get; set; }
        [Required]
        public List<string> Attendees { get; set; } = new List<string>();

    }
}

for some reason it still doesnt work so i came with this idea but i dont know if it is a good practice i created a class DateTimeConverter

using System;
using System.Text.Json;
using System.Text.Json.Serialization;

namespace EventEnroll.Utils
{
    public class DateTimeConverter : JsonConverter<DateTime>
    {
        public override DateTime Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
        {
            return DateTime.Parse(reader.GetString());
        }

        public override void Write(Utf8JsonWriter writer, DateTime value, JsonSerializerOptions options)
        {
            writer.WriteStringValue(value.ToString("dd/MM/yyyy"));
        }
    }
}

using System;
using System.Text.Json;
using System.Text.Json.Serialization;

namespace EventEnroll.Utils
{
    public class DateTimeConverter : JsonConverter<DateTime>
    {
        public override DateTime Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
        {
            return DateTime.Parse(reader.GetString());
        }

        public override void Write(Utf8JsonWriter writer, DateTime value, JsonSerializerOptions options)
        {
            writer.WriteStringValue(value.ToString("dd/MM/yyyy"));
        }
    }
}

Angius•16mo ago

Well, if you really want, you could have the Date be a string and convert the format during selection

PedroOP•16mo ago

and i added to the program.cs

builder.Services.AddControllers().AddJsonOptions(options =>
{
    options.JsonSerializerOptions.Converters.Add(new DateTimeConverter());
});

builder.Services.AddControllers().AddJsonOptions(options =>
{
    options.JsonSerializerOptions.Converters.Add(new DateTimeConverter());
});

Angius•16mo ago

var stuff = await context.Things
    .Where(...)
    .Select(t => new ThingDto {
        // ...
        Date = t.Date.ToString("dd/MM/yyyy"),
    })
    .FirstOrDefaultAsync();

var stuff = await context.Things
    .Where(...)
    .Select(t => new ThingDto {
        // ...
        Date = t.Date.ToString("dd/MM/yyyy"),
    })
    .FirstOrDefaultAsync();

What I wonder, though, is why not pass the date like it should be In ISO8601 format And let the frontend worry about formatting

PedroOP•16mo ago

its just the specification for this internship project i got

Angius•16mo ago

Ah, oof, my condolences

PedroOP•16mo ago

otherwise i would keep it

Angius•16mo ago

Schools and companies utilize the shittiest standards sometimes

PedroOP•16mo ago

yeah

Angius•16mo ago

In that case, do this

PedroOP•16mo ago

so, i came with that solution . is this ok?

Angius•16mo ago

Does it work?

PedroOP•16mo ago

it does haha

Angius•16mo ago

Then it's fine

PedroOP•16mo ago

just dont know if they will look at it and find strange or bad practices

Angius•16mo ago

Not using ISO8601 is a bad practice already And they clearly don't care So

PedroOP•16mo ago

hmm yeah ok then

Angius•16mo ago

Even then, this is how you would do it Whatever you needed to format, tapping into the converter options will do the trick And it's fine

Accord•15mo ago

Was this issue resolved? If so, run /close - otherwise I will mark this as stale and this post will be archived until there is new activity.

Gaming

Programming

❔ problem with DateTime format