您可以使用ES2015 模板文字。但是，变量应该在使用之前定义。

You can use ES2015 template literals. But, the variables should be defined before using them.

var name1 = "Phil";
var name2 = "Amy";
var templateString = `Hello ${name1}, my name is ${name2}`;

console.log(templateString);
document.body.innerHTML = templateString;

对于ES2015之前的版本，您可以使用正则表达式替换变量。为此，可以创建具有搜索替换值的对象，并且 字符串#replace 。

For pre-ES2015, you can use regex to replace the variables. For this, an object having the search-replace values can be created and String#replace with function as parameter can be used.

正则表达式 \ {（[^}] *）\} 可用于匹配大括号包围的字符串。

The regex \{([^}]*)\} can be used to match the strings which are surrounded by the curly brackets.

// Create an object of the key-value of search-replace
var obj = {
    name1: "Phil",
    name2: "Amy"
};

var templateString = "Hello {name1}, my name is {name2}";

// Use replace with callback function
var result = templateString.replace(/\{([^}]*)\}/g, function($0, $1) {
    return obj[$1] || $0; // If replacement found in object use that, else keep the string as it is
});

console.log(result);
document.body.innerHTML = result;

RegEx说明：

1. \ {：匹配 {括号文字


2. （[ ^}] *）：匹配}以外的任何内容零次或多次，并将其添加到第一个捕获的组中。


3. \} ：匹配} 括号文字


4. g ：全局标志。匹配此模式后面的所有可能字符串。

1. \{: Match { bracket literal
2. ([^}]*): Match anything other than } zero or more number of times and add this in the first captured group.
3. \}: Match } bracket literal
4. g: Global flag. Match all possible strings that follows this pattern.

注意： $ 0 是完整的字符串，即 {foo} 和 $ 1 是第一个被捕获的组 foo 。

Note: $0 is the complete string i.e. {foo} and $1 is the first captured group foo.