diff --git a/check.go b/check.go
new file mode 100644
index 0000000..66b3cb7
--- /dev/null
+++ b/check.go
@@ -0,0 +1,81 @@
+package productrpc
+
+import (
+	"strconv"
+	"time"
+)
+
+/*
+ * 检查商品状态
+ * 2020/09/16
+ */
+func CheckStatus(productInfo map[string]string, arrival_time string) (int, string) {
+	if productInfo["Status"] == "0" { //是否在售
+		return 8405, "商品已下架"
+		if productInfo["Status"] == "2" { //是否在售
+			return 8405, "商品已售罄"
+		}
+	}
+	if productInfo["Status"] != "1" { //是否在售
+		return 8405, "商品未上架"
+	}
+	if productInfo["AutoOnSale"] == "1" {
+		if productInfo["EndSaleTime"] != "0" && productInfo["EndSaleTime"] != "" { //销售截止日期
+			end_sale_time, _ := strconv.ParseInt(productInfo["EndSaleTime"], 10, 64)
+			if time.Unix(end_sale_time, 0).Before(time.Now()) { //截止日期在当前时间之前
+				return 8407, "商品已过有效期"
+			}
+		}
+		if productInfo["StartSaleTime"] != "0" && productInfo["StartSaleTime"] != "" { //销售开始日期
+			end_sale_time, _ := strconv.ParseInt(productInfo["StartSaleTime"], 10, 64)
+			if time.Unix(end_sale_time, 0).After(time.Now()) { //开始日期在当前时间之后
+				return 8406, "商品未开售"
+			}
+		}
+	}
+	if productInfo["ValidityType"] == "1" { //用户选定使用日期
+		if arrival_time == "" {
+			return 10005, "请选择使用日期"
+		} else {
+
+			advance, _ := strconv.Atoi(productInfo["Advance"]) //提前几天
+
+			arrival_time_int64, err := strconv.ParseInt(arrival_time, 10, 64)
+			var release_time_int64, end_time_int64 int64 = 0, 0
+			now := time.Now().Unix()
+
+			if err != nil { // 转换失败
+				return 10005, "日期错误"
+			}
+			if arrival_time_int64 < now { //不能在当前时间之前
+				return 10005, "日期选择错误"
+			}
+
+			if productInfo["Releasetime"] != "" && productInfo["Releasetime"] != "0" {
+				release_time_int64, _ = strconv.ParseInt(productInfo["Releasetime"], 10, 64)
+			}
+			if productInfo["Endtime"] != "" && productInfo["Endtime"] != "0" {
+				end_time_int64, err = strconv.ParseInt(productInfo["Endtime"], 10, 64)
+				if err == nil {
+					if advance > 0 {
+						end_time_int64 = end_time_int64 - int64(advance*24*3600) //提前几天截止预约
+						if end_time_int64 < now {
+							return 8409, "已截止购买"
+						}
+					}
+				}
+			}
+
+			if release_time_int64 > 0 && arrival_time_int64 < release_time_int64 { //未到服务时间
+				return 10006, "请选择" + time.Unix(release_time_int64, 0).Format("2006-01-02") + "之后的日期"
+			}
+			if end_time_int64 > 0 {
+				if arrival_time_int64 > end_time_int64 { //已过服务时间
+					return 10006, "请选择" + time.Unix(end_time_int64, 0).Format("2006-01-02") + "之前的日期"
+				}
+			}
+
+		}
+	}
+	return 0, ""
+}