Question

TranslationItem模型：

[DataContract]
public class TranslationItem : CloneableBaseEntity<TranslationItem>, IValidatableObject
{

    public int TranslationId { get; set; }
    public Translation Translation { get; set; }

    public int Lcid { get; set; }        

    private string _text;
    public string Text
    {
        get { return _text; }
        set
        {
            _text = value;
            RaisePropertyChanged("Text");
        }
    }

    public IEnumerable<ValidationResult> Validate(ValidationContext validationContext)
    {
        var t = validationContext.ObjectInstance as TranslationItem;   
        return t.Translation.Validate(validationContext);               
    }
}

翻译模型：

[DataContract]
public class Translation : CloneableBaseEntity<Translation>, IValidatableObject
{
    private static int _englishLcid = 9;

    private  ObservableCollection<TranslationItem> _translations;
    [DataMember]
    public virtual ObservableCollection<TranslationItem> Translations
    { 
        get{
            return _translations;
        }
        set
        {
            _translations = value;
            foreach (TranslationItem ti in _translations)
            {
                ti.PropertyChanged += ti_PropertyChanged;
            }
        }
    }

    ...
    public IEnumerable<ValidationResult> Validate(ValidationContext validationContext){ 

        Translation t;
        if(validationContext.ObjectInstance.GetType()== typeof(Translation))
            t = validationContext.ObjectInstance as Translation;
        else
            t =( validationContext.ObjectInstance as TranslationItem).Translation;

        if (!t.EnglishNotRequried)
        {
            if (!t.TranslationDict.ContainsKey(_englishLcid) || String.IsNullOrEmpty(t.TranslationDict[_englishLcid].Text))
            {
                yield return new ValidationResult("EnglishTranslationMissing");
            }
        }
    }
}

我的迁移配置类中的Seed方法

protected override void Seed(DbContext context)
{
    int deLcid = new CultureInfo("en").LCID;
    int enLcid = new CultureInfo("en").LCID;


    TranslationItem enStd = context.TranslationItems.FirstOrDefault(ti => ti.Text == "Standard" && ti.Lcid == enLcid)
                            ?? new TranslationItem { Text = "Standard", Lcid = enLcid };

    TranslationItem deStd = context.TranslationItems.FirstOrDefault(ti => ti.Text == "Standard" && ti.Lcid == deLcid)
                            ?? new TranslationItem { Text = "Standard", Lcid = deLcid };

    context.Translations.AddOrUpdate(
        t => t.Translations,
        new Translation
            {
                Translations = new ObservableCollection<TranslationItem>
                    {
                        enStd,
                        deStd
                    }
            });

    context.SaveChanges();

    context.EventTypes.AddOrUpdate(
        et => et.Name,
        new EventType
        {
            Name = context.Translations.FirstOrDefault(t => t.Translations.Any(x => x.Lcid == enLcid && x.Text == "Standard") &&
                                                            t.Translations.Any(x => x.Lcid == deLcid && x.Text == "Standard") )
        });             
}

当我想更新数据库

时，我收到以下错误

Unable to create a constant value of type 'PQS.Model.TranslationItem'. Only primitive types or enumeration types are supported in this context.

我不太确定如何解决这个问题。我已经尝试首先插入我的TranslationItems，但是当我这样做时，验证失败，因为我猜想需要翻译FK。

请帮助!!

Answer 1

通过我自己的一个小黑客修复它（不完全是我的首选解决方案，但现在可以使用）

我的问题：似乎使用AddOrUpdate(...)我只能比较原始类型或枚举类型。

所以我添加了一个名为SeedId的额外ID来识别我的实体。

所以我的种子方法中的代码现在非常简单：

foreach (EventType eventtype in PqsDbContext.getStdEventTypes())
{
    context.EventTypes.AddOrUpdate(et => et.SeedId, eventtype);
}

EF迁移种子 - 无法创建“Application.Model.TranslationItem”类型的常量值

1 个答案: