javascript - 如何在 JS 中替换子字符串的所有实例但仅替换整个世界？

Question

例如这个函数

function replaceAll(str,x,y){
    return str.split(x).join(y);
}

var x="My cat have a hat a its head.";

replaceAll(x,"at","on")

将从这里返回

My cat have a hat at its head.

到此

My con have a hon on its head.

但我想返回

My cat have a hat on its head.

Answer 1

使用单词边界正则表达式定义您的函数:

function replaceAll(str,x,y){
    return str.split(new RegExp("\\b"+x+"\\b")).join(y);
}

然后:

repl = replaceAll(x,"at","on")
//=> My cat have a hat on its head.