总是报错误呢
为什么按他写的,总是报String interpolation produces a debug description for an optional value; did you mean to make this explicit? Use 'String(describing:)' to silence this warning
为什么按他写的,总是报String interpolation produces a debug description for an optional value; did you mean to make this explicit? Use 'String(describing:)' to silence this warning
2018-04-25
这个是字符串拼接的时候最后没有判断吧,因为可能最后一个字符串是可选字符串 可以参考 https://www.jianshu.com/p/cf65a376dc7b
举报