提取字符串中的数字- FineReport帮助文档 - 全面的报表使用教程和学习资料 (fanruan.com)
参考
REPLACE(INDEXOFARRAY(SPLIT(REPLACE(ds1.select(days)," "," ")," "),2),"号")
单元格设置
=JOINARRAY(GREPARRAY(split(B7, ""), regexp(item, "[0-9]")), "")