javascript - nodejs报错 打开localhost:3000 就报错

Answer 1

Your error message is very clear. If slice is empty or not present, it means that the slice field must be used in your js. It may be that your array uses this interception method, and the array may be empty. Yes, so an error was reported

Answer 2

Learn to read error messages: Cannot read property 'slice' of null

This means you used the slice method on null. Output the string/array you used the slice method to see if it is null