Question

以下是我的课程

public class Item
{
    public int ItemID { get; set; }

    [Required(ErrorMessage = "Unit of measure1 is required.")]
    public int Uom1Id { get; set; }
    public UnitOfMeasure Uom1 { get; set; }

    [Required(ErrorMessage = "Unit of measure2 is required.")]
    public int Uom2Id { get; set; }
    public UnitOfMeasure Uom2{ get; set; }
}

public class UnitOfMeasure
{
    public int UnitOfMeasureID { get; set; }
    public string MeasureName { get; set; }
}

我的初始化程序如下：

    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        modelBuilder.Conventions.Remove<PluralizingTableNameConvention>();

        modelBuilder.Entity<Item>().HasRequired(x => x.StockUnitOfMeasure)
       .WithMany()
       .HasForeignKey(x => x.StockUnitOfMeasureId).WillCascadeOnDelete(false);

        modelBuilder.Entity<Item>().HasRequired(x => x.PurchaseUnitOfMeasure)
           .WithMany()
           .HasForeignKey(x => x.PurchaseUnitOfMeasureId).WillCascadeOnDelete(false);

    }

创建代码：

<div class="editor-label">
        @Html.LabelFor(model => model.Uom1Id, "Stock Unit Of Measure")
    </div>
    <div class="editor-field">
        @Html.DropDownList("Uom1Id", String.Empty)
        @Html.ValidationMessageFor(model => model.Uom1Id )
    </div>

我是EF的新手，我不知道为什么属性[Required]对字段Uom1Id和Uom2Id不起作用，但它适用于我其他类中的其他字段。

具有键＆＃39; Uom1Id＆＃39;的ViewData项。是的输入＆＃39; System.Int32＆＃39;但必须是类型＆＃39; IEnumerable的＆＃39;

由于

Answer 1

int不能为null，因为它是一种有价值的类型，因此无需将Required属性添加到Uom1Id和Uom2Id。对于UI，您可以创建一个视图模型，其中Uom1Id和Uom2Id将为int?（可为空）。

asp.net mvc代码优先。需要下拉列表

1 个答案: