Javascript：在特定位置替換字符串

Question

我有一個像這樣的字符串：

var str = "Hello, it is a <test>12345</test> and it's fun";

我想將“ 12345”替換為“ ****”。

該腳本必須考慮到包含在和之間的字符串永遠不相同的事實。

Answer 1

您可以使用此正則表達式：

str = str.replace(/(<test>).*?(?=<\/test>)/, '$1*****');
//=> "Hello, it is a <test>*****</test> and it's fun"

如果您不希望超前，請在兩側使用捕獲組：

str = str.replace(/(<test>).*?(<\/test>)/, '$1*****$2');
//=> "Hello, it is a <test>*****</test> and it's fun"

Answer 2

如果數字不一定總是被包含在<test>標記之間，則這是解決相同問題的另一種方法。

var str = "Hello, it is a <test>12345</test> and it's fun";

var numberPattern = /(\<\w+\>)(\d+)(\<\/\w+\>)/gi;

str = str.replace(numberPattern, "$1****$3");

// str is now "Hello, it is a <test>****</test> and it's fun"