为什么ModelState.IsValid在使用帖子存储一个到多个数据时返回“false”。我正在使用ViewModel和EditorTemplate来显示那些正在编辑的数据。在我的情况下测试(一) - 问题(很多)。如果只存储test,那么modelstate是有效的,但是如果我在测试中存储问题,模型状态就会变得无效......在整个地方查找信息,但是无法理解为什么这是无效的。由于许多教程显示这是映射一对多关系的方式,为什么我不能以这种方式发布数据?
模型
public class Test
{
public Test()
{
this.Questions = new List<Question>();
}
//some excluded for brevity
[Required]
public string Name { get; set; }
[Key]
[DatabaseGenerated(DatabaseGeneratedOption.Identity)]
public int Id { get; set; }
[Required]
public DateTime TestDate { get; set; }
public int TestTypeId { get; set; }
public virtual ICollection<Question> Questions { get; set; }
public virtual Type Type { get; set; }
}
}
public class Question
{
[Key]
[DatabaseGenerated(DatabaseGeneratedOption.Identity)]
public int QuestionID { get; set; }
public int TestID { get; set; }
public string Question { get; set; }
public virtual Test Test { get; set; }
}
ViewModel(使用viewmodel,因为它有助于从存储在数据库中的数据生成下拉列表)
public class TestData
{
public Test Test { get; set; }
public Question Question { get; set; }
public IEnumerable<TestType> TestTypes { get; set; }
public List<string> Questions { get; set; }
}
问题的编辑模板
@model Project.Models.CustomQuestion
<div>
@Html.HiddenFor(a => a.QuestionID)
@Html.HiddenFor(a => a.TestID)
@Html.HiddenFor(a => a.Test)
@Html.EditorFor(a => a.Question)
</div>
查看(编辑)
@model Project.ViewModels.TestData
@using (Html.BeginForm()) {
@Html.AntiForgeryToken()
@Html.ValidationSummary(true)
<fieldset>
<legend>Event</legend>
@Html.HiddenFor(a => a.Test.Id)
<div class="editor-field">
@Html.EditorFor(model => model.Test.Name
</div>
<div class="editor-field">
@Html.EditorFor(model => model.Test.TestDate)
</div>
<div>
@Html.DropDownListFor(model => model.Test.TestTypeId, new SelectList(Model.TestTypes, "Id", "Name"))
</div>
<div class="editor-field">
if 5 questions are stored 5 textboxes with questions will appear
@Html.EditorFor(model => model.Test.Questions)
</div>
<p>
<input type="submit" value="Save" />
</p>
</fieldset>
}
控制器
public ActionResult Edit(int id = 0)
{
var viewModel = new ViewModels.TestData
{
Test = db.Tests.Find(id),
TestTypes = db.TestTypes
};
return View(viewModel);
}
[HttpPost]
public ActionResult Edit(TestData testData)
{
if (ModelState.IsValid) //returns "false" if testData.Event.Questions > 0
{
db.Entry(testtData).State = EntityState.Modified;
db.SaveChanges();
return RedirectToAction("Index");
}
return View(testData);
}