如何在 post 方法中反序列化 asp.net 核心 api 中的 json 数组？

Question

how i can solve this problem (serialized/ and deserialize JSON array and store and read from sql server)? thank you

i created asp.net core api that connected to angular project and occurs problem when i want post json that contains json array(ingredient):

 { "RecepieName": "3222",
"Ingredient": [ { "ingredientName": "43243", "value": "33", "measure": "" },
{ "ingredientName": "565" , "value": "3", "measure": "" }],
"CookingTime": 3,
"Level": "advance", 
"ServingPerson": 3, 
"RecepieAbstration": "good food",
"RecepieText": "",
"CreateDate": "2021-01-04T12:37:51.948",
"ModifiedDate": "2021-01-04T12:37:51.948" }

when i use postman for test I encounter this error:

postman error

you can see my model, dto and action post in controller:

Model:

  public class Recepie
    {
    [Key]
    public int ID { get; set; }
    [Required]
    public string RecepieName { get; set; }
    [Required]
    public string Ingredient { get; set; }   // include ingredientName / value / measure array
    [Required]
    public int CookingTime { get; set; }
    [Required]
    public string Level { get; set; }
    [Required]
    public int ServingPerson { get; set; }
    [Required]
    public string RecepieAbstration { get; set; }
    [Required]
    public string RecepieText { get; set; }
    [Required]
    public string NutritionalInformation { get; set; }
    [Required]
    public string Tags { get; set; }
  
    public DateTime CreateDate { get; set; }

    public DateTime ModifiedDate { get; set; }
    }

DTO: RecepieCreateDto

    public class RecepieCreateDto
{

    public string RecepieName { get; set; }

    //public int MentorID { get; set; }

    public string Ingredient { get; set; }


    public int CookingTime { get; set; }

    public string Level { get; set; }

    public int ServingPerson { get; set; }

    public string RecepieAbstration { get; set; }

    public string RecepieText { get; set; }

    public string Tags { get; set; }

    public DateTime CreateDate { get; set; }

    public DateTime ModifiedDate { get; set; }
}

Action Post:

        //Post api/recepie
    [HttpPost]
    public ActionResult <RecepieReadDto> CreateRecepie(RecepieCreateDto recepieCreateDto)
    {
        var recepieModel = _mapper.Map<Recepie>(recepieCreateDto);
        _repository.CreateRecepieObject(recepieModel);
        _repository.SaveChange();
        var recepieReadDto = _mapper.Map<RecepieReadDto>(recepieModel);
        return CreatedAtRoute(nameof(GetRecepieByID), new { Id = recepieReadDto.ID }, recepieReadDto);
        // return Ok(recepieModel);
    }

Answer 1

You are passing array for Ingredient but expecting string . Please change Ingredient to be List<Ingredient> where Ingredient is your new object which has name, value and messure. For example:

 public class Ingredient { [Key] int Id {get; set; } string IngredientName { get; set; } string Value { get; set; } string Measure { get; set; } }

UPDATE: please update the DTO model respectively and use it in RecepieCreateDto

 public class IngredientDTO
 {
 string IngredientName { get; set; }
 string Value { get; set; }
 string Measure { get; set; }
 }

Answer 2

in RecepieCreateDto class Ingredient is a string but in your request json Ingredient is a array. so change RecepieCreateDto class or request json.

"[{\"ingredientName\": \"43243\", \"value\": \"33\", \"measure\": \"\" },{ \"ingredientName\": \"565\" , \"value\": \"3\", \"measure\": \"\" }]"

OR

    public IList<Ingredient> Ingredient { get; set; }

Answer 3

You need to create a class for Ingredient property.

public class Ingredient {
    public string IngredientName { get; set; }
    public string Value { get; set; } // This might be an int, you can change this on your purpose.
    public string Measure { get; set; } // This might be an int, you can change this on your purpose.
}

Looks like the ingredient you posting is a collection type so making Ingredient List<> or any other collection type might do it.

public class RecepieCreateDto
{

    public string RecepieName { get; set; }

    //public int MentorID { get; set; }

    public List<Ingredient> Ingredient { get; set; }


    public int CookingTime { get; set; }

    public string Level { get; set; }

    public int ServingPerson { get; set; }

    public string RecepieAbstration { get; set; }

    public string RecepieText { get; set; }

    public string Tags { get; set; }

    public DateTime CreateDate { get; set; }

    public DateTime ModifiedDate { get; set; }
}

You might need to make similar changes to your Recepie model after these changes.

Answer 4

you can implement solution like below code ;
1 : Create View model For input Api;

  

 public class RecepieCreateViewModel
        {
    
            public string RecepieName { get; set; }
    
            public List<Ingredient> Ingredient { get; set; }
    
            public int CookingTime { get; set; }
    
            public string Level { get; set; }
    
            public int ServingPerson { get; set; }
    
            public string RecepieAbstration { get; set; }
    
            public string RecepieText { get; set; }
    
            public string NutritionalInformation { get; set; }
    
            public string Tags { get; set; }
    
            public DateTime CreateDate { get; set; }
    
            public DateTime ModifiedDate { get; set; }
        }

   

 public class Ingredient
    {
        public string ingredientName { get; set; }
        public string value { get; set; }
        public string measure { get; set; }
    }


2 : Create Dto Model

public class RecepieCreateDto
{

    public string RecepieName { get; set; }

    public string Ingredient { get; set; }

    public int CookingTime { get; set; }

    public string Level { get; set; }

    public int ServingPerson { get; set; }

    public string RecepieAbstration { get; set; }

    public string RecepieText { get; set; }

    public string NutritionalInformation { get; set; }

    public string Tags { get; set; }

    public DateTime CreateDate { get; set; }

    public DateTime ModifiedDate { get; set; }

}

3 : Cast Ingredient Model ToJson Object In Api And Create New RecepieCreateDto Like Below Code

  var result=Newtonsoft.Json.JsonConvert.SerializeObject(recepieCreateDto.Ingredient);
        

   RecepieCreateDto readDto = new RecepieCreateDto
    {
        CookingTime = recepieCreateDto.CookingTime,
        Level = recepieCreateDto.Level ,
        ModifiedDate = recepieCreateDto.ModifiedDate ,
        NutritionalInformation = recepieCreateDto.NutritionalInformation ,
        RecepieAbstration = recepieCreateDto.RecepieAbstration ,
        RecepieName = recepieCreateDto.RecepieName ,
        RecepieText = recepieCreateDto.RecepieText ,
        ServingPerson = recepieCreateDto.ServingPerson ,
        CreateDate = recepieCreateDto.CreateDate ,
        Tags = recepieCreateDto.Tags ,
        Ingredient=result,

    };