js-URL参数的获取

1、获取单个参数：

function getParam(name, url) {
    if(typeof name !== 'string') return false;
    if (!url) url = window.location.href;
    // 当遇到name[xx]时，对方括号做一下转义为 name\[xxx\]，因为下面还需要使用name做正则
    name = name.replace(/[\[\]]/g, '\\$&');
    var regex = new RegExp('[?&]' + name + '(=([^&#]*)|&|#|$)');
    var results = regex.exec(url);
    if (!results) return null;
    if (!results[2]) return '';
    return decodeURIComponent(results[2].replace(/\+/g, " "));
}

getParam('query','https://juejin.im/search?query=hello&time=2017-11-12')

//输出：hello

2、获取多个参数：

function getParams(names, url) {
    if(typeof name !== 'string') return false;
    var names = names.split(' ');
    var result = {};
    var i = 0,
        len = names.length;
    if (names.length === 0) return false;
    for (; i < len; i++) {
        result[names[i]] = getParam(names[i], url);
    }
    return result;
}
getParams('query time','https://juejin.im/search?query=hello&time=2017-11-12')

//输出：{query: "hello", time: "2017-11-12"}

3、设置单个参数：

function setParam(name, val, url) {
    if(typeof name !== 'string') return false;
    if (!url) url = window.location.href;
    var _name = name.replace(/[\[\]]/g, '\\$&');
    var value = name + '=' + encodeURIComponent(val);
    var regex = new RegExp(_name + '=[^&]*');
    var urlArr = url.split('#');
    var result = '';

    if(regex.exec(url)){
        result =  url.replace(regex, value);
    }else{
        result = urlArr[0]+'&'+value+ (urlArr[1] || '');
    }

    return result
}
setParam('query','world','https://juejin.im/search?query=hello&time=2017-11-12')

// output: 
// "https://juejin.im/search?query=world&time=2017-11-12"

4、设置多个参数：

function setParams(obj, url) {
    var result = url || '';
    if (Object.prototype.toString.call(obj) !== '[object Object]') return false;
    for (var name in obj) {
        result = setParam(name, obj[name], result);
    }
    return result;
}
setParams({a:111,b:222,query:'world'},'https://juejin.im/search?query=hello&time=2017-11-12')

// output: 
// "https://juejin.im/search?query=world&time=2017-11-12&a=111&b=222"