如何从javascript中的字符串中提取参数（指定的模式字符串）

Question

I need to extract parameter name from the url path. parameters are inside {} or follow the first ?(questionmark) or follow & mark in the url.

the url path need to be extracted is in such format :

/tt/{pa}/{pb}/?p1=9888&p2=9&p3=98

thus the parameters are pa , pb , p1 , p1 , p3

Answer 1

Quickest way I can think of is this:

[{?&][^}=]+

Debuggex Demo

Now I'm also capturing the { or ? or & character preceding it, so you'd have to cut that off afterwards:

 var inp = '/tt/{pa}/{pb}/?p1=9888&p2=9&p3=98' var found = inp.match(/[{?&][^}=]+/g).map(function(p){ return p.substring(1); }); document.write(found.join('<br />')); 

And if you expect something like /tt/{pa=}/{pb}/?p1={9888&p2=9&p3=98 where pa= is a valid param name and/or {9888 is a valid value, you'd be in trouble. But I doubt this is a serious limitation.

Answer 2

Simple example for extracting separately search variables and variables from path:

function extractSearch(search) {
    var result = {};

    search = search || window.location.search;

    if (search.length) {
        search = search.substr(1).split('&');

        for (var i = 0; i < search.length; i++) {
            search[i] = search[i].split('=');
            result[decodeURIComponent(search[i][0])] = decodeURIComponent(search[i][1]);
        }
    }

    return result;
}

function extractFromPath(pattern, url) {
    var keys = [],
        result = {},
        i;

    url = url || window.location.pathname;

    pattern = pattern.replace(/{([^}]+)}/g, function($0, $1) {
        keys.push($1);
        return '([^/]+)';
    });

    pattern = url.match(new RegExp('^' + pattern));

    for (i = 0; i < keys.length; i++) {
        result[keys[i]] = pattern[i + 1];
    }

    return result;
}

Example of use:

// Object {a: "10", b: "20"}
extractSearch('?a=10&b=20');

// Object {pa: "1", pb: "2"}
extractFromPath('/tt/{pa}/{pb}', '/tt/1/2/?p1=9888&p2=9&p3=98');

Eventually you can combine it by:

function getParameters(pattern, path) {
    var result,
        tmp;

    path = path.split('?');

    result = extractFromPath(pattern, path[0]);

    if (path[1] !== void 0) {
        tmp = extractSearch('?' + path[1]);

        for (var param in tmp) {
            result[param] = tmp[param];
        }
    }

    return result;
}

// Object {pa: "1", pb: "2", a: "10", b: "20"}
getParameters('/tt/{pa}/{pb}', '/tt/1/2?a=10&b=20');