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为什么在我的ASP.NET MVC站点中再添加一次ModelState错误?

asp.net-mvc asp.net c#

quakkels · 技术社区 · 14 年前

我有一个相当复杂的模型,我使用它来呈现表单并使用模型的元信息元信息执行验证。

视图模型具有表单中包含的子对象列表。子对象基于以下内容:

[Table]
public class FieldInstance
{
    [Column(IsPrimaryKey = true, IsDbGenerated = true, AutoSync = AutoSync.OnInsert)]
    public long fiID { get; set; }
    [Column]
    public string fiLabel { get; set; }
    [Column]
    public bool fiIsRequired { get; set; }

    [DisplayName("alpha-numeric value")]
    [Column]
    public string fiStrValue { get; set; }

    [DisplayName("date/time value")]
    [Column]
    public DateTime? fiDateTimeValue { get; set; }

    [DisplayName("integer value")]
    [Column]
    public long? fiIntValue { get; set; }

    [DisplayName("decimal value")]
    [Column]
    public decimal? fiDecValue { get; set; }
    [Column]
    public int fiOrder { get; set; }
    [Column]
    public long fiStreamEntryID { get; set; }  // FK
    [Column]
    public long fiFieldTypeID { get; set; }    // FK

    // Relationship (many FieldInstances to one StreamEntry)
    // using EntityRef<StreamEntry> and ThisKey
    // which is "This" table's FK
    private EntityRef<StreamEntry> _StreamEntry;
    [System.Data.Linq.Mapping.Association(Storage = "_StreamEntry", ThisKey = "fiStreamEntryID")]
    public StreamEntry StreamEntry
    {
        get { return this._StreamEntry.Entity; }
        set { this._StreamEntry.Entity = value; }
    }

    // Relationship (one FieldInstance to one FieldType)
    // using EntityRef<FieldTypes> and ThisKey
    private EntityRef<FieldTypes> _FieldType;
    [System.Data.Linq.Mapping.Association(Storage = "_FieldType", ThisKey = "fiFieldTypeID")]
    public FieldTypes FieldTypes
    {
        get { return this._FieldType.Entity; }
        set { this._FieldType.Entity = value; }
    }

我用的是 Html.EditorFor() 语句为列表中的每个项呈现局部视图模板。

如果我把文字输入 Datetime 那么,菲尔德 Html.ValidationSummary() 显示:

â¢The value 'asd' is not valid for date/time value.
â¢The value 'asd' is not valid for date/time value.

我的问题是错误被添加到 ModelState 两次而不是一次。这是控制器操作:

    [HttpPost]
    public ActionResult EntryEdit(StreamEntry form)
    {
        // Get values
        StreamEntry entry = 
            form.seID == 0
            ? new StreamEntry()
            : genesisRepository.GetEntryByID(form.seID);

        // Get Stream for new entry
        if (form.seID == 0)
            entry.Stream = genesisRepository.GetStreamByID(form.StreamID);

        //Validate
        TryUpdateModel(entry);

        if (ModelState.IsValid)
            return RedirectToAction("EntryList", new { id = entry.StreamID });
        else
            return View(entry);
    }

为什么错误是由于存在不正确的输入而触发的,从而导致错误的两个实例被添加到“ModelState”中?

1 回复 | 直到 14 年前

Darin Dimitrov 14 年前

当默认模型绑定器试图解析 StreamEntry form 动作参数和第二次调用 TryUpdateModel 同一类型的方法( StreamEntry ). 所以要么使用动作参数要么 TryUpdateModel公司 方法,但决不能两者兼得。就我个人而言,我总是使用动作参数,从不使用 TryUpdateModel公司 方法。

所以要纠正你的错误:

[HttpPost]
public ActionResult EntryEdit(StreamEntry model)
{
    if (!ModelState.IsValid)
    {
        // the model was not valid => redisplay the form so that 
        // the user can fix errors
        return View(model);
    }
    // Remark: might need to load the model's corresponding stream
    // from the repository if its values weren't posted

    // the model was valid => update it in the database
    genesisRepository.Update(model);
    return RedirectToAction("EntryList", new { id = model.StreamID });
}