从“GET”参数中获取值（JavaScript）

Eldon McGuinness的这个Gist是我目前见过的JavaScript查询字符串解析器中最完整的实现。

不幸的是，它是作为jQuery插件编写的。

我将其重写为原生JS并进行了一些改进：

function parseQuery(str) {
  var qso = {};
  var qs = (str || document.location.search);
  // Check for an empty querystring
  if (qs == "") {
    return qso;
  }
  // Normalize the querystring
  qs = qs.replace(/(^\?)/, '').replace(/;/g, '&');
  while (qs.indexOf("&&") != -1) {
    qs = qs.replace(/&&/g, '&');
  }
  qs = qs.replace(/([\&]+$)/, '');
  // Break the querystring into parts
  qs = qs.split("&");
  // Build the querystring object
  for (var i = 0; i < qs.length; i++) {
    var qi = qs[i].split("=");
    qi = qi.map(function(n) {
      return decodeURIComponent(n)
    });
    if (typeof qi[1] === "undefined") {
      qi[1] = null;
    }
    if (typeof qso[qi[0]] !== "undefined") {

      // If a key already exists then make this an object
      if (typeof (qso[qi[0]]) == "string") {
        var temp = qso[qi[0]];
        if (qi[1] == "") {
          qi[1] = null;
        }
        qso[qi[0]] = [];
        qso[qi[0]].push(temp);
        qso[qi[0]].push(qi[1]);

      } else if (typeof (qso[qi[0]]) == "object") {
        if (qi[1] == "") {
          qi[1] = null;
        }
        qso[qi[0]].push(qi[1]);
      }
    } else {
      // If no key exists just set it as a string
      if (qi[1] == "") {
        qi[1] = null;
      }
      qso[qi[0]] = qi[1];
    }
  }
  return qso;
}

// DEMO
console.log(parseQuery("?foo=bar&foo=boo&roo=bar;bee=bop;=ghost;=ghost2;&;checkbox%5B%5D=b1;checkbox%5B%5D=b2;dd=;http=http%3A%2F%2Fw3schools.com%2Fmy%20test.asp%3Fname%3Dst%C3%A5le%26car%3Dsaab&http=http%3A%2F%2Fw3schools2.com%2Fmy%20test.asp%3Fname%3Dst%C3%A5le%26car%3Dsaab"));

另请参见这个 Fiddle。

// http:localhost:8080/path?param_1=a&param_2=b
var getParamsMap = function () {
    var params = window.location.search.split("&");
    var paramsMap = {};
    params.forEach(function (p) {
        var v = p.split("=");
        paramsMap[v[0]]=decodeURIComponent(v[1]);
    });
    return paramsMap;
};

// -----------------------

console.log(getParamsMap()["param_1"]);  // should log "a"     

window.location.search.slice(1).split('&').reduce((res, val) => ({...res, [val.split('=')[0]]: val.split('=')[1]}), {})

function getUrlParam(paramName) {
    var match = window.location.search.match("[?&]" + paramName + "(?:&|$|=([^&]*))");
    return match ? (match[1] ? decodeURIComponent(match[1]) : "") : null;
}

这些特殊情况的处理与URLSearchParams一致：

• 如果参数缺失，返回null。

• 如果参数存在但没有"="（例如"?param"），返回""。

注意！如果有可能参数名包含特殊的URL 或 正则表达式字符（例如来自用户输入），您需要对其进行转义。可以使用以下方式轻松完成：

function getUrlParamWithSpecialName(paramName) {
    return getUrlParam(encodeURIComponent(paramName).replace(/[.*+?^${}()|[\]\\]/g, "\\$&"));
}

window.location.href.split("?")

Array.prototype.slice.call(window.location.href.split("?"), 1) 

返回您的URL参数数组

var paramArray = Array.prototype.slice.call(window.location.href.split(/[?=]+/), 1);
var paramObject = paramArray.reduce(function(x, y, i, a){ (i%2==0) ?  (x[y] = a[i+1]) : void 0; return x; }, {});

稍微啰嗦些，可能有点hacky，但也是功能性的。paramObject包含所有参数作为js对象映射的结果。

<h1>Hey User! Can you please copy the value out of the location bar where it says like, &m=2? Thanks! And then, if you could...paste it in the box below and click the Done button?</h1>
<input type='text' id='the-url-value' />
<input type='button' value='This is the Done button. Click here after you do all that other stuff I wrote.' />

<script>
//...read the value on click

好的，严肃地说... 我找到了这段代码，它似乎很好用:

http://www.developerdrive.com/2013/08/turning-the-querystring-into-a-json-object-using-javascript/

function queryToJSON() {
    var pairs = location.search.slice(1).split('&');

    var result = {};
    pairs.forEach(function(pair) {
        pair = pair.split('=');
        result[pair[0]] = decodeURIComponent(pair[1] || '');
    });

    return JSON.parse(JSON.stringify(result));
}

var query = queryToJSON();

以下是将URL查询参数解析为对象的AngularJS源代码：

function tryDecodeURIComponent(value) {
  try {
    return decodeURIComponent(value);
  } catch (e) {
    // Ignore any invalid uri component
  }
}

function isDefined(value) {return typeof value !== 'undefined';}

function parseKeyValue(keyValue) {
  keyValue = keyValue.replace(/^\?/, '');
  var obj = {}, key_value, key;
  var iter = (keyValue || "").split('&');
  for (var i=0; i<iter.length; i++) {
    var kValue = iter[i];
    if (kValue) {
      key_value = kValue.replace(/\+/g,'%20').split('=');
      key = tryDecodeURIComponent(key_value[0]);
      if (isDefined(key)) {
        var val = isDefined(key_value[1]) ? tryDecodeURIComponent(key_value[1]) : true;
        if (!hasOwnProperty.call(obj, key)) {
          obj[key] = val;
        } else if (isArray(obj[key])) {
          obj[key].push(val);
        } else {
          obj[key] = [obj[key],val];
        }
      }
    }
  };
  return obj;
}

alert(JSON.stringify(parseKeyValue('?a=1&b=3&c=m2-m3-m4-m5')));

window.location.query = function query(arg){
  q = parseKeyValue(this.search);
  if (!isDefined(arg)) {
    return q;
  }      
  if (q.hasOwnProperty(arg)) {
    return q[arg];
  } else {
    return "";
  }
}

// assuming you have this url :
// http://www.test.com/t.html?a=1&b=3&c=m2-m3-m4-m5

console.log(window.location.query())

// Object {a: "1", b: "3", c: "m2-m3-m4-m5"}

console.log(window.location.query('c'))

// "m2-m3-m4-m5"

我们可以更简单地获取c参数的值，而无需循环所有参数，请参见以下jQuery代码以获取参数。

1. 获取参数值：

var url = "www.test.com/t.html?a=1&b=3&c=m2-m3-m4-m5";

url.match(**/(c=)[0-9A-Za-z-]+/ig**)[0].replace('c=',"")

(或者)

url.match(**/(c=)[0-z-]+/ig**)[0].replace('c=',"")

返回字符串

"m2-m3-m4-m5"

2. 替换参数值：

var url = "www.test.com/t.html?a=1&b=3&c=m2-m3-m4-m5";

url.replace(**/(c=)[0-9A-Za-z-]+/ig, "c=m2345"**)

function getParamValue(param) {
    var urlParamString = location.search.split(param + "=");
    if (urlParamString.length <= 1) return "";
    else {
        var tmp = urlParamString[1].split("&");
        return tmp[0];
    }
}

export const getURLParams = location => {
    const searchParams = new URLSearchParams(location.search)
    const params = {}

    for (let key of searchParams.keys()) {
        params[key] = searchParams.get(key)
    }

    return params
}

console.log(getURLParams({ search: '?query=someting&anotherquery=anotherthing' }))

// --> {query: "someting", anotherquery: "anotherthing"}