/// <summary>
 /// 检查合同信息信息是否存在
 /// </summary>
 /// <param name="predicate">检查谓语表达式</param>
 /// <param name="id">更新的合同信息编号</param>
 /// <returns>合同信息是否存在</returns>
 public bool CheckContractExists(Expression <Func <Contract, bool> > predicate, int id = 0)
 {
     return(ContractRepository.CheckExists(predicate, id));
 }