必应每日一图直接获取及接口

必应官网：https://cn.bing.com/

返回Json数据的接口
https://cn.bing.com/HPImageArchive.aspx?format=js&idx=0&n=1

返回结果:

{
    "images": [
        {
            "startdate": "20190604",
            "fullstartdate": "201906041600",
            "enddate": "20190605",
            "url": "/th?id=OHR.PeruvianRainforest_ZH-CN4066508593_1920x1080.jpg&rf=LaDigue_1920x1080.jpg&pid=hp",
            "urlbase": "/th?id=OHR.PeruvianRainforest_ZH-CN4066508593",
            "copyright": "秘鲁亚马逊坦博帕塔国家保护区中的树冠 (© Patrick Brandenburg/Tandem Stills + Motion)",
            "copyrightlink": "http://www.bing.com/search?q=%E6%A0%91%E5%86%A0&form=hpcapt&mkt=zh-cn",
            "title": "",
            "quiz": "/search?q=Bing+homepage+quiz&filters=WQOskey:%22HPQuiz_20190604_PeruvianRainforest%22&FORM=HPQUIZ",
            "wp": true,
            "hsh": "73a0f621c340498bb1abbfb4abf79258",
            "drk": 1,
            "top": 1,
            "bot": 1,
            "hs": []
        }
    ],
    "tooltips": {
        "loading": "正在加载...",
        "previous": "上一个图像",
        "next": "下一个图像",
        "walle": "此图片不能下载用作壁纸。",
        "walls": "下载今日美图。仅限用作桌面壁纸。"
    }
}

其中字段url就是图片地址，但是只有一半，需要加一个前缀。
地址前缀https://www.bing.com/ 和http://s.cn.bing.net都可以。
即完整的图片地址为
http://s.cn.bing.net/th?id=OHR.PeruvianRainforest_ZH-CN4066508593_1920x1080.jpg&rf=LaDigue_1920x1080.jpg&pid=hp
或者
https://www.bing.com/th?id=OHR.PeruvianRainforest_ZH-CN4066508593_1920x1080.jpg&rf=LaDigue_1920x1080.jpg&pid=hp