从List <func <t，bool =“”>＆gt;更改返回类型到一个Func <t，bool =“”>

Question

我有一个获取规则对象列表并生成List＆gt;的函数。 这是我的代码：

public static List<Func<T, bool>> CompileRule<T>(List<Rule> rules)
    {
        var compiledRules = new List<Func<T, bool>>();

        // Loop through the rules and compile them against the properties of the supplied shallow object 
        rules.ForEach(rule =>
        {
            var genericType = Expression.Parameter(typeof(T));
            var key = Expression.Property(genericType, rule.ComparisonPredicate);
            var propertyType = typeof(T).GetProperty(rule.ComparisonPredicate).PropertyType;
            var value = Expression.Constant(Convert.ChangeType(rule.ComparisonValue, propertyType));
            var binaryExpression = Expression.MakeBinary(rule.ComparisonOperator, key, value);
            compiledRules.Add(Expression.Lambda<Func<T, bool>>(binaryExpression, genericType).Compile());
        });

        // Return the compiled rules to the caller
        return compiledRules;
    }

我想更改函数以返回在已编译函数和（＆amp;＆amp;）之间生成的Func，并在Funcs之间返回Func<T, bool>。

规则类看起来像这样：

 public class Rule
{
    ///
    /// Denotes the rules predictate (e.g. Name); comparison operator(e.g. ExpressionType.GreaterThan); value (e.g. "Cole")
    /// 
    public string ComparisonPredicate { get; set; }
    public ExpressionType ComparisonOperator { get; set; }
    public string ComparisonValue { get; set; }

    /// 
    /// The rule method that 
    /// 
    public Rule(string comparisonPredicate, ExpressionType comparisonOperator, string comparisonValue)
    {
        ComparisonPredicate = comparisonPredicate;//property name
        ComparisonOperator = comparisonOperator;//operation
        ComparisonValue = comparisonValue;//target value
    }
}