From 69cda4e029225726f5ce193010e11a1fa7f796f3 Mon Sep 17 00:00:00 2001
From: wdvxdr <wdvxdr@foxmail.com>
Date: Wed, 27 Jan 2021 16:08:59 +0800
Subject: [PATCH] fix null json

---
 global/filter.go | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/global/filter.go b/global/filter.go
index ef8588a..fdcf5fb 100644
--- a/global/filter.go
+++ b/global/filter.go
@@ -25,12 +25,18 @@ func (m MSG) Get(s string) MSG {
 		}
 		return MSG{"__str__": v} // 用这个名字应该没问题吧
 	}
-	return MSG{}
+	return nil // 不存在为空
 }
 
 //String 将消息Map转化为String。若Map存在key "__str__",则返回此key对应的值,否则将输出整张消息Map对应的JSON字符串
 func (m MSG) String() string {
+	if m == nil {
+		return "" // 空 JSON
+	}
 	if str, ok := m["__str__"]; ok {
+		if str == nil {
+			return "" // 空 JSON
+		}
 		return fmt.Sprint(str)
 	}
 	str, _ := json.MarshalToString(m)