尝试字符串操作:

var txt = "I expect five hundred dollars ($500). and new brackets ($600)";
var newTxt = txt.split('(');
for (var i = 1; i < newTxt.length; i++) {
    console.log(newTxt[i].split(')')[0]);
}

或regex(与上面的相比，它有点慢)

var txt = "I expect five hundred dollars ($500). and new brackets ($600)";
var regExp = /\(([^)]+)\)/g;
var matches = txt.match(regExp);
for (var i = 0; i < matches.length; i++) {
    var str = matches[i];
    console.log(str.substring(1, str.length - 1));
}

对于货币符号后面的数字:\(.+\s*\d+\s*\)应该可以

或\(.+\)表示括号内的任何内容

尝试字符串操作:

var txt = "I expect five hundred dollars ($500). and new brackets ($600)";
var newTxt = txt.split('(');
for (var i = 1; i < newTxt.length; i++) {
    console.log(newTxt[i].split(')')[0]);
}

或regex(与上面的相比，它有点慢)

var txt = "I expect five hundred dollars ($500). and new brackets ($600)";
var regExp = /\(([^)]+)\)/g;
var matches = txt.match(regExp);
for (var i = 0; i < matches.length; i++) {
    var str = matches[i];
    console.log(str.substring(1, str.length - 1));
}

简单: (? <价值 >(?<=\().*(?=\)))

我希望我能帮上忙。

选择:

var str = "I expect five hundred dollars ($500) ($1).";
str.match(/\(.*?\)/g).map(x => x.replace(/[()]/g, ""));

→ (2) ["$500", "$1"]

如果需要，可以用方括号或花括号代替方括号

简单的解决方案

注意:这个解决方案可以用于这个问题中只有一个“(”和“)”的字符串。

("I expect five hundred dollars ($500).").match(/\((.*)\)/).pop();

在线演示(jsfiddle)