private void Length() { Expression <Func <Student, bool> > exp = it => SqlFunc.Length("aaaa") > 1; SqlServerExpressionContext expContext = new SqlServerExpressionContext(); expContext.Resolve(exp, ResolveExpressType.WhereSingle); var value = expContext.Result.GetString(); var pars = expContext.Parameters; base.Check(value, pars, "(LEN(@MethodConst0) > @Const1 )", new List <SugarParameter>() { new SugarParameter("@MethodConst0", "aaaa"), new SugarParameter("@Const1", 1) }, "Length error"); }