这种情况用循环递归代替Javascript。

Question

我正在研究一个字符串，它是这样的(这是一个很长的字符串，有500+个值，它将以递增的方式运行，如这个例子所示。) )

Select "start_date", "pmcounter"[1] as "pmcounter[1]", "pmcounter"[2] as "pmcounter[2]" ,"pmcounter"[31] as "pmcounter[31]" from view

我想让这个字符串看起来像

Select "start_date", "pmcounter"[1] as "pmcounter_1", "pmcounter"[2] as "pmcounter_2" ,"pmcounter"[31] as "pmcounter_31" from view

为此，我做了这段代码。(我是一个非常初级的水平，你可以从我的代码中看出：) )

var fields = "Select \"start_date\", \"pmcounter\"[1] as \"pmcounter[1]\", \"pmcounter\"[2] as \"pmcounter[2]\" ,\"pmcounter\"[31] as \"pmcounter[31]\" from view";

fields = fields.replace(/\[1\]\"/,'_1\"')
fields = fields.replace(/\[2\]\"/,'_2\"')
fields = fields.replace(/\[3\]\"/,'_3\"')
fields = fields.replace(/\[31\]\"/,'_31\"')
// const regex = new RegExp("ReGeX"+n+"ReGeX");
console.log(fields);

输出。

Select "start_date", "pmcounter"[1] as "pmcounter_1", "pmcounter"[2] as "pmcounter_2" ,"pmcounter"[31] as "pmcounter_31" from view

你能告诉我一个简单的方法吗？一些For循环。

Answer 1

你可以使用捕捉到的组，并在替换时使用回溯引用

\[(\d+)\]"
  ^^^^^
    --------- Capture group, which we are referencing by `$1` in replace callback

const fields = "Select \"start_date\", \"pmcounter\"[1] as \"pmcounter[1]\", \"pmcounter\"[2] as \"pmcounter[2]\" ,\"pmcounter\"[31] as \"pmcounter[31]\" from view";

console.log(fields.replace(/\[(\d+)\]"/g, '_[' + "$1" + ']"'))