要在js中想要替换替换模板中的${}，可以使用字符串的replace()方法结合正则表达式或者函数来实现替换操作。

以下是两种常见的替换方式： 使用正则表达式：

方法一：

const template = "Hello, ${name}! Today is ${day}.";
const data = {name: "John",day: "Monday"
};const result = template.replace(/\${(.*?)}/g, (match, key) => data[key]);
console.log(result);  // 输出: Hello, John! Today is Monday.

方法二：

const template = "Hello, ${name}! Today is ${day}.";
const data = {name: "John",day: "Monday"
};const result = template.replace(/\${(.*?)}/g, (match, key) => {return data.hasOwnProperty(key) ? data[key] : match;
});
console.log(result);  // 输出: Hello, John! Today is Monday.