This solution, in effect, gives the receiving system a hint as to which values are standard (including casing and spelling) but in fact allows any value in the string field.

实际上，该解决方案提示接收系统哪些值是标准的(包括包装和拼写)。但实际上字符串字段可以存放任何值。

youdao

Set the usage string to show a hint for when invalid parameters are submitted.

设置usage字符串来显示一个提示，以免提交无效的参数。

youdao