javascript - JavaScript replace()方法美元符号

Question

我有一个类似于aman/gupta的字符串，我想将其替换为aman$$gupta，为此，我正在使用JavaScript replace方法，如下所示:

let a = "aman/gupta"
a = a.replace("/", "$")
console.log(a) // 'aman$gupta'

a = "aman/gupta"
a = a.replace("/", "$$")
console.log(a) // 'aman$gupta'

a = "aman/gupta"
a = a.replace("/", "$$$")
console.log(a) // 'aman$$gupta'

为什么第一种情况和第二种情况相同，并且当我使用$$$而不是$$时得到了预期的结果？

Answer 1

这是因为$$插入了"$"。

因此，您需要使用:

a = "aman/gupta";
a = a.replace("/", "$$$$"); // "aman$$gupta"

请参阅以下special patterns:

Pattern   Inserts
$$        Inserts a "$".
$&        Inserts the matched substring.
$`        Inserts the portion of the string that precedes the matched substring.
$'        Inserts the portion of the string that follows the matched substring.
$n        Where n is a non-negative integer lesser than 100, inserts the nth
            parenthesized submatch string, provided the first argument was a
            RegExp object.