diff --git a/servers/boe-server-all/src/main/java/com/xboe/school/study/service/impl/StudyCourseServiceImpl.java b/servers/boe-server-all/src/main/java/com/xboe/school/study/service/impl/StudyCourseServiceImpl.java
index 18992cb8..1bd1b11b 100644
--- a/servers/boe-server-all/src/main/java/com/xboe/school/study/service/impl/StudyCourseServiceImpl.java
+++ b/servers/boe-server-all/src/main/java/com/xboe/school/study/service/impl/StudyCourseServiceImpl.java
@@ -418,7 +418,7 @@ public class StudyCourseServiceImpl implements IStudyCourseService{
 
 			}
 		}
-		if(StringUtils.isNotBlank(str)){
+		if(StringUtils.isNotBlank(str1)){
 			str1.deleteCharAt(str1.length()-1);
 		}