How to use regular expressions to ReFactor Code and remove redundant Code

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Before refact: a lot of duplicate code

After refact: use map to eliminate duplicate code.

Var usRegx = / XXXX/. is required for each check in the current branch. In fact, a regular expression object is defined literally, which is more expensive than defining a String. In fact, it is not necessary to define map every time, you can define map on a global attribute of controller.

Execute this code to see the performance difference between string constants and regular expression literals:

Var N = 100000000 console.time ("normal string"); for (var I = 0; I < N; iTunes +) {var a = "a";} console.timeEnd ("normal string"); console.time ("regular exp"); for (var I = 0; I < N; iTunes +) {var b = / ^ [0-9] {5} $| ^ [0-9] {5}-[0-9] {4} $/;} console.timeEnd ("regular exp")

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