asp.net core系列之模型绑定和验证方法

//例如:请求URL
http://contoso./movies/edit/2
  
//映射到movies/edit/2
public IActionResult Edit(int? id)

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

  [Required]
  [StringLength(100)]
  public string Title { get; set; }

  [ClassicMovie(1960)]
  [DataType(DataType.Date)]
  public DateTime ReleaseDate { get; set; }

  [Required]
  [StringLength(1000)]
  public string Description { get; set; }

  [Range(0, 999.99)]
  public decimal Price { get; set; }

  [Required]
  public Genre Genre { get; set; }

  public bool Preorder { get; set; }
}

/// <summary>
  /// 自定义验证
  /// </summary>
  public class ClassicMovieAttribute : ValidationAttribute
  {
    private int _year;

    /// <summary>
    /// 验证规则值
    /// </summary>
    /// <param name="year"></param>
    public ClassicMovieAttribute(int year)
    {
      _year = year;
    }

    protected override ValidationResult IsValid(object value, ValidationContext validationContext)
    {
      Movie movie = (Movie)validationContext.ObjectInstance;

      //用户不能将 1960 年以后发行的电影的流派设置为 Classic
      if (movie.Genre == "Classic" && movie.ReleaseDate.Year > _year)
      {
        return new ValidationResult(GetErrorMessage());
      }

      return ValidationResult.Suess;
    }

    private string GetErrorMessage()
    {
      return $"Classic movies must have a release year earlier than {_year}.";
    }
  }

<div class="form-group">
<label asp-for="ReleaseDate" class="control-label"></label>
<input asp-for="ReleaseDate" class="form-control" />
<span asp-validation-for="ReleaseDate" class="text-danger"></span>
</div>

<form action="/Movies/Create" method="post">
  <div class="form-horizontal">
    <h4>Movie</h4>
    <div class="text-danger"></div>
    <div class="form-group">
      <label class="col-md-2 control-label" for="ReleaseDate">ReleaseDate</label>
      <div class="col-md-10">
        <input class="form-control" type="datetime"
        data-val="true" data-val-required="The ReleaseDate field is required."
        id="ReleaseDate" name="ReleaseDate" value="" />
        <span class="text-danger field-validation-valid"
        data-valmsg-for="ReleaseDate" data-valmsg-replace="true"></span>
      </div>
    </div>
  </div>
</form>

$.get({
  url: "https://url/that/returns/a/form",
  dataType: "html",
  error: function(jqXHR, textStatus, errorThrown) {
    alert(textStatus + ": Couldn't add form. " + errorThrown);
  },
  suess: function(newFormHTML) {
    //添加表单newFormHTML
    var container = document.getElementById("form-container");
    container.insertAdjacentHTML("beforeend", newFormHTML);
    //验证第一个表单
    var forms = container.getElementsByTagName("form");
    var newForm = forms[forms.length - 1];
    //分析表单的 data- 属性
    $.validator.unobtrusive.parse(newForm);
  }
})

var newFormHTML = "<form action=\"create\" method=\"post\">";
newFormHTML += "<div class=\"form-group\">";
newFormHTML += "<label asp-for=\"Title\" class=\"control- label\"></label>";
newFormHTML += "<input type=\"text\" data-val=\"true\" data-val-required=\"The Title field is required.\" id = \"Title\" name= \"Title\">";
newFormHTML += "<span class=\"text- danger field- validation - valid\" data-valmsg-for=\"Title\" data-valmsg-replace=\"true\"></span>";
newFormHTML += "</div>";
newFormHTML += "<div class=\"form-group\" >";
newFormHTML += "<input type=\"submit\" value=\"Save\" class=\"btn btn-primary\" />";
newFormHTML += "</div >";
newFormHTML += "</form>";

$("#idbtn").click(function () {
  var container = document.getElementById("form-container");
  container.insertAdjacentHTML("beforeend", newFormHTML);

  var forms = container.getElementsByTagName("form");
  var newForm = forms[forms.length - 1];
  //分析表单的 data- 属性
  $.validator.unobtrusive.parse(newForm);
});

@model StudyMVCDemo.Models.Movie
@{
  ViewData["Title"] = "Create";
}
<h1>Create</h1>

<div class="row">
  <input value="动态加载表单" type="button" id="idbtn" />
  <div id="form-container" class="col-md-4">

  </div>
</div>
<div>
  <a asp-action="Index">Back to List</a>
</div>
@section Scripts {
  @{await Html.RenderPartialAsync("_ValidationScriptsPartial");}
  <script src="~/js/dynamic-form-validate.js"></script>
}

$.get({
  url: "https://url/that/returns/a/control",
  dataType: "html",
  error: function(jqXHR, textStatus, errorThrown) {
    alert(textStatus + ": Couldn't add control. " + errorThrown);
  },
  suess: function(newInputHTML) {
     //向表单动态添加Input控件
    var form = document.getElementById("my-form");
    form.insertAdjacentHTML("beforeend", newInputHTML);
     //移除现有的验证
    $(form).removeData("validator")  // Added by jQuery Validate
        .removeData("unobtrusiveValidation");  // Added by jQuery Unobtrusive Validation
     //重新分析整个表单
    $.validator.unobtrusive.parse(form);
  }
})

/// <summary>
  /// 自定义验证
  /// </summary>
  public class ClassicMovieAttribute : ValidationAttribute,IClientModelValidator
  {
    private int _year;

    /// <summary>
    /// 年份参考值
    /// </summary>
    /// <param name="year"></param>
    public ClassicMovieAttribute(int year)
    {
      _year = year;
    }

    protected override ValidationResult IsValid(object value, ValidationContext validationContext)
    {
      Movie movie = (Movie)validationContext.ObjectInstance;

      //用户不能将 1960 年以后发行的电影的流派设置为 Classic
      if (movie.Genre == "Classic" && movie.ReleaseDate.Year > _year)
      {
        return new ValidationResult(GetErrorMessage());
      }

      return ValidationResult.Suess;
    }

    private string GetErrorMessage()
    {
      return $"Classic movies must have a release year earlier than {_year}.";
    }

    public void AddValidation(ClientModelValidationContext context)
    {
      if (context == null)
      {
        throw new ArgumentNullException(nameof(context));
      }

      MergeAttribute(context.Attributes, "data-val", "true");
      MergeAttribute(context.Attributes, "data-val-classicmovie", GetErrorMessage());

      var year = _year.ToString(CultureInfo.InvariantCulture);
      MergeAttribute(context.Attributes, "data-val-classicmovie-year", year);
    }

    private bool MergeAttribute(IDictionary<string, string> attributes, string key, string value)
    {
      if (attributes.ContainsKey(key))
      {
        return false;
      }

      attributes.Add(key, value);
      return true;
    }
  }

<input class="form-control" type="date" 
data-val="true" 
data-val-classicmovie="Classic movies must have a release year earlier than 1960."
data-val-classicmovie-year="1960" 
data-val-required="The ReleaseDate field is required." 
id="ReleaseDate" name="ReleaseDate" value="1989-02-12">

//添加验证方法
$.validator.addMethod('classicmovie',function (value, element, params) {
     //value ，是当前验证的元素的值。
     //element 元素本身。
     //params 是传入的参数(options.rules)
    var genre = $("#form1").find("#Genre").val(),
      year = params[0],
      date = new Date(value);
    if (genre.length > 0 && genre === 'Classic') {
      // Since this is a classic movie, invalid if release date is after given year.
      return date.getFullYear() <= year;
    }
    return true;
  });

//注册一个适配器，参数1是适配器名称,参数2是验证规则的名称
$.validator.unobtrusive.adapters.add('classicmovie',['year'],function (options) {
    //适配器规则绑定到jquery validation上面
    options.rules['classicmovie'] = [parseInt(options.params['year'])];
    options.messages['classicmovie'] = options.message;
  });