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FieldInfo field = <some valid string field on type T>;
ParameterExpression targetExp = Expression.Parameter(typeof(T), "target");
ParameterExpression valueExp = Expression.Parameter(typeof(string), "value");

如何编译lambda表达式以将"target"参数上的字段设置为"value"？

我在运行时为给定的成员生成编译的getter方法.现在,我的代码只是假设getter方法的结果是一个字符串(适用于测试).但是,我想用我编写的自定义转换器类来完成这项工作,请参阅下面的"ConverterBase"参考,我已经添加了.

我无法弄清楚如何将转换器类的调用添加到我的表达式树.

    public Func<U, string> GetGetter<U>(MemberInfo info)
    {
        Type t = null;
        if (info is PropertyInfo) 
        {
            t = ((PropertyInfo)info).PropertyType;
        }
        else if (info is FieldInfo)
        {
            t = ((FieldInfo)info).FieldType;
        }
        else
        {
            throw new Exception("Unknown member type");
        }

        //TODO, replace with ability to specify in custom attribute
        ConverterBase typeConverter = new ConverterBase();

        ParameterExpression target = Expression.Parameter(typeof(U), "target");
        MemberExpression memberAccess = Expression.MakeMemberAccess(target, info);

        //TODO here, make the expression call "typeConverter.FieldToString(fieldValue)"

        LambdaExpression getter = Expression.Lambda(memberAccess, target);

        return (Func<U, string>)getter.Compile();
    }

我正在寻找第二个TODO区域的内容(我可以处理第一个:)). …