参考原文:
http://m.bubuko.com/infodetail-465328.html
//定义追加的过滤变量 var searchWhere = PredicateBuilder.New<实体类>(); if (!string.IsNullOrWhiteSpace(custName)) searchWhere = searchWhere.And(t => t.CustomerName.Contains(custName)); if (!string.IsNullOrWhiteSpace(carModel)) searchWhere = searchWhere.And(t => t.CarType.Contains(carModel));