泛型类作为非泛型类中的属性答案

【问题标题】：Generic class as property in a nongeneric class泛型类作为非泛型类中的属性
【发布时间】：2019-06-13 06:51:51
【问题描述】：

我有一个自定义的 GridView，我想设置一些规则来显示错误。我想做这样的事情：

var grid = new MyGridView();
grid.DataSource = new List<MyClass>();
grid.InitErrorRegistrator<MyClass>()
   .RegisterRule(column1, x => x.Property1 == 12)
   .RegisterRule(column2, x => x.Property2 == "Test");

因此，当我填充网格时，我希望在使用不适当的值填充行值时看到错误。

我有这样的事情：


internal class ErrorRegistrator
{
   internal GenericErrorRegistrator<T> Init<T>()
   {
      return new GenericErrorRegistrator<T>();
   }

   /*Here I think I could use methods to get values from GenericErrorRegistrator<T> dictionary like:*/
   internal bool CheckRule(string column, object row)
   {
      return GenericErrorRegistrator.CheckRule(column, row);
   }
}

public class GenericErrorRegistrator<T>
{
   private readonly Dictionary<string, object> _errorRules = new Dictionary<string, object>();
   internal Dictionary<string, object> ErrorRules => _errorRules;

   public void RegisterErrorRule(string columnName, Func<T, bool> func)
   {
      _errorRules.Add(columnName, func);
   }
   public bool CheckRule(string column, object row)
   {
       Func<T, bool> func = _errorRules[column]
       return func((T) row);  
   }
}

MyGridView

public class MyGridView : GridView
{
    internal ErrorRegistrator ErrorRegistrator = new ErrorRegistrator();

/*Here I think should be something like*/
    public GenericErrorRegistrator<T> InitErrorRegistrator<T>()
    {
        return ErrorRegistrator.Init<T>();
    }

}

最后我有一个 GridController 类，它分析是否有任何规则并将其应用于一行：

public class MyGridCurrencyDataController : CurrencyDataController
{
   public override ErrorInfo GetErrorInfo(int controllerRow, int column)
   {
      var info = base.GetErrorInfo(controllerRow, column);
      DataColumnInfo dataColumnInfo = Columns[column];
      BandedGridColumn gridColumn = GridColumns.ColumnByFieldName(dataColumnInfo.Name);

      if (HasErrRules ?? false)
      {
        object row = _view.GetRow(controllerRow);
        /*I think here I need something like this*/
        bool showError = _view.ErrorRegistrator.CheckRule(gridColumn.Name, row );                       
        if (showError)
           SetError(new RowColumnErrorEventArgs(info, controllerRow, gridColumn));
        else
           ClearError(new RowColumnErrorEventArgs(info, controllerRow, gridColumn));
       }
       _view.FillRowColumnError(controllerRow, gridColumn, info);
       return info;
     }
}

我怎样才能做到这一点，这可能吗？

【问题讨论】：

标签： c# .net winforms generics gridview

【解决方案1】：

这就是我所拥有的。我稍后会测试性能，但至少它可以工作。

myGridView.InitRegistrator<Job>()
   .RegisterRule(column1, x => string.IsNullOrEmpty(x.Code))
   .RegisterRule(column2, x => string.IsNullOrEmpty(x.Name))

MyGridView

public class MyGridView : GridView
{
   internal ErrorRegistrator ErrorRegistrator = new ErrorRegistrator();
   public GenericErrorRegistrator<T> InitRegistrator<T>(params Func<T, bool>[] funcs)
   {
      return ErrorRegistrator.Init<T>();
   }
}

错误注册器

    internal class ErrorRegistrator
    {
        internal bool HasRules => _registrator.HasRules();

        private BaseGenericErrorRegistrator _registrator;
        internal GenericErrorRegistrator<T> Init<T>()
        {
            var errorRegistrator = new GenericErrorRegistrator<T>();
            _registrator = errorRegistrator;
            return errorRegistrator;
        }

        public bool CheckRule(string columnName, object row)
        {
            return _registrator.CheckRule(columnName, row);
        }
    }

    public abstract class BaseGenericErrorRegistrator
    {
        internal abstract bool HasRules();
        internal abstract bool CheckRule(string columnName, object row);
    }

    public class GenericErrorRegistrator<T> : BaseGenericErrorRegistrator
    {
        private readonly Dictionary<string, Func<T, bool>> _rules = new Dictionary<string, Func<T, bool>>();
        public GenericErrorRegistrator<T> RegisterRule(string columnName, Func<T, bool> func)
        {
            _rules.Add(columnName, func);
            return this;
        }

        internal override bool HasRules()
        {
            return _rules.Any();
        }

        internal override bool CheckRule(string columnName, object row)
        {
            return _rules.TryGetValue(columnName, out Func<T, bool> func) && func((T) row);
        }
    }

然后我可以使用ErrorRegistrator字段检查规则

【讨论】：