Question

我有Parent Model类和viewModel类。 Parent Model类有GetViewModel（）方法，我试图继承Parent类并覆盖Child类中的GetViewModel（）。但是，它抛出一个无限异常。

父ViewModel类：

public class ParentViewModel
{
    public IEnumerable<string> Choices { get; set; }
    public object Value { get; set; }
    public IMetaField MetaField { get; set; }
    public bool IsRequired { get; set; }
    public bool HasOtherChoice { get; set; }
    public string ValidationAttributes { get; set; }
    public string RequiredViolationMessage { get; set; }
    public string CssClass { get; set; }
}

父模型类：

public class ChildModel : ParentModel
{
    public string CorticonEntityName { get; set; }
    public string CorticonFieldName { get; set; }

    public override object GetViewModel(object value, IMetaField metaField)
    {
        this.Value = value;
        return (object)new ChildViewModel()
        {
            Choices = this.DeserializeChoices(),
            Value = value,
            MetaField = this.MetaField,
            HasOtherChoice = this.HasOtherChoice,
            IsRequired = (this.ValidatorDefinition.Required.HasValue && this.ValidatorDefinition.Required.Value),
            ValidationAttributes = this.BuildValidationAttributesString(),
            RequiredViolationMessage = this.ValidatorDefinition.RequiredViolationMessage,
            CssClass = this.CssClass
        };
    }
}

我创建了两个子类ChildModel类和ChildViewModel类，这些类继承了父元素。

我想覆盖父类的GetViewModel（），所以我已完成如下操作并且工作正常。

ChildViewModel类：

public class ChildViewModel:ParentViewModel
{
    public string CorticonEntityName { get; set; }
    public string CorticonFieldName { get; set; }
}

ChildModel类：

public class ChildModel : ParentModel
{
    public string CorticonEntityName { get; set; }
    public string CorticonFieldName { get; set; }

    public override object GetViewModel(object value, IMetaField metaField)
    {
        this.Value = value;
        return (object)new ChildViewModel()
        {
            Choices = this.DeserializeChoices(),
            Value = value,
            MetaField = this.MetaField,
            HasOtherChoice = this.HasOtherChoice,
            IsRequired = (this.ValidatorDefinition.Required.HasValue && this.ValidatorDefinition.Required.Value),
            ValidationAttributes = this.BuildValidationAttributesString(),
            RequiredViolationMessage = this.ValidatorDefinition.RequiredViolationMessage,
            CssClass = this.CssClass,
            CorticonEntityName=this.CorticonEntityName,
            CorticonFieldName=this.CorticonFieldName
        };
    }
}

但我不想再像父GetViewModel（）那样在子类GetViewModel（）中设置所有属性。我想重用Parent类方法并在Child类中设置新属性，所以我尝试了如下但是它会抛出无限循环。

ChildViewModel类：

public class ChildViewModel:ParentViewModel
{
    public string CorticonEntityName { get; set; }
    public string CorticonFieldName { get; set; }
    CheckboxesFieldViewModel baseObject { get; set; }
}

ChildModel类：

public class ChildModel : ParentModel
{
    public string CorticonEntityName { get; set; }
    public string CorticonFieldName { get; set; }
    CheckboxesFieldViewModel baseObject { get; set; }

    public override object GetViewModel(object value, IMetaField metaField)
    {
        object objBase=this.GetViewModel(value,metaField);
        return (object)new ChildViewModel ()
        {
            objParent=objBase,
            CorticonEntityName = this.CorticonEntityName,
            CorticonFieldName = this.CorticonFieldName
        };
    }
}

如何在不重新设置属性的情况下重用Parent类GetViewModel（）。

Answer 1

你的罪魁祸首是：

object objBase=this.GetViewModel(value,metaField);

你一遍又一遍地递归调用相同的方法，炸毁堆栈。如果要调用父方法，则需要使用base关键字：

object objBase = base.GetViewModel(value, metaField);

覆盖Child类中的ParentModel类方法

1 个答案: