python 列表索引越界怎么处理_tuple索引号越界报错的解决方法 IndexError: Replacement index 12 out of range for positional arg...

前几天遇到tuple索引号越界的报错，调试了好久都没解决，幸亏柳老师帮我分析后搞定啦，感激～在这里记录一下

背景

代码用 python 抓取网站信息的数据，导入本地数据库(MySQL)时 遇到下标越界问题

上图：

```python

IndexError: Replacement index 12 out of range for positional args tuple

虽然是在format这行报的错，但实际错的是上面values的

位置参数的{0}就表示format函数中的第一个值，依次类推。

format里面就11个值，所以调用它的对象里的索引最多到{10} ，即下面所示

sqlstr += "values('{0}','{1}','{2}','{3}','{4}','{5}','{6}','{7}','{8}','{9}','{10}')"

再次运行后很开心，这个bug解决啦

我之前以为要跟字典里结构的位置相匹配，就改成 {12} {16} {17} 了，哇咔咔，我的错

真就是基础不牢，地动山摇，要系统地学一下python噢

python的 self参数 就像 java 里的 this 哈

代码优化

柳老师还顺便帮我优化了一下代码，嘿嘿嘿

sqlstr = "insert into fy_successors (name,sex,cover_pic,details,updated_at,created_at,province,project,born_year,cate,batch)"

sqlstr += "values({1},{2},{3},{4},{6},{7},{9},{12},{14},{16},{17})"

sqlstr.format("'"+dict_successor['name']+"'","'"+dict_successor['sex']+"'","'"+dict_successor['cover_pic']+"'","'"+pymysql.escape_string(dict_successor['details'])+"'","'"+dict_successor['updated_at']+"'","'"+dict_successor['created_at']+"'","'"+dict_successor['province']+"'","'"+dict_successor['project']+"'","'"+dict_successor['born_year']+"'","'"+dict_successor['cate']+"'","'"+dict_successor['batch']+"'")

这样写的可读性很低，要把引号放在位置参数两边，更简洁 ‘{ 1 }’

修改后：

sqlstr = "insert into fy_successors (name,sex,cover_pic,details,updated_at,created_at,province,project,born_year,cate,batch)"

sqlstr += "values('{1}','{2}','{3}','{4}','{5}','{6}','{7}','{8}','{9}','{10}')"

sqlstr.format(dict_successor['name'],dict_successor['sex'],dict_successor['cover_pic'],pymysql.escape_string(dict_successor['details']),dict_successor['updated_at'],dict_successor['created_at'],dict_successor['province'],dict_successor['project'],dict_successor['born_year'],dict_successor['cate'],dict_successor['batch'])

怎么样，是不是简洁很多呀