$.ajax({
type: "GET",
url: "https://e.dangdang.com/media/api.go?action=getPcChapterInfo&epubID=1900465429&permanentId=2.0170111163553175e+34&consumeType=1&platform=3&deviceType=Android&deviceVersion=5.0.0&channelId=70000&platformSource=DDDS-P&fromPaltform=ds_android&deviceSerialNo=html5&clientVersionNo=5.8.4&token=&chapterID=2&pageIndex=0&locationIndex=3&wordSize=2&style=2&autoBuy=0&chapterIndex=",
dataType: "json",
success: function (response) {
let data = JSON.parse(response.data.chapterInfo).snippet,
regex = '<span class="[^"]+" style="left:([0-9]+)px; bottom:([0-9]+)px; ">([^<]+)<\/span>',
result = [],
str = "";

data.match(RegExp(regex, 'g')).forEach(item => {
let info = item.match(RegExp(regex));
result[info[2]] = result[info[2]] || [];
result[info[2]][info[1]] = info[3];
});

result.forEach(item => {
str = item.join("") + str;
});
console.log(str);
}
});