PHP解码数据库中的JSON字符串返回NULL

Question

我有自己的网站，使用来自Google CSE (自定义搜索引擎)的API，因为Google限制每天对免费用户进行100次调用，所以我想将Google API中的JSON结果存储到我的数据库中，以保存我的每天100次调用配额，所以当API调用时，我只是从我的数据库中获得。

我想把这个JSON从我的数据库打印到一个循环中

<?php
$search = mysql_query("SELECT * FROM jsondata WHERE id_jsondata = 1");
$jsondata = mysql_fetch_assoc($search);
$json = json_decode($jsondata['jsondata'], true);
foreach ($json as $data) {
echo $data['link'];
}
?>

但是它没有发生，当我尝试var_dump($json)时，它是空的。

JSON在我的数据库中转换为字符串，如下所示。

[{"kind":"customsearch#result","title":"Tekken 7 - Full-Length SDCC 2014 Trailer - YouTube","htmlTitle":"<b>Tekken 7</b> - Full-Length SDCC 2014 <b>Trailer</b> - YouTube","link":"https://www.youtube.com/watch?v=yTm6BV8RT9A","displayLink":"www.youtube.com","snippet":"Jul 25, 2014 ... Check out the full-length Tekken 7 trailer straight from the Bandai Namco Games Fighting Game Panel at San Diego Comic-Con 2014! Followu00a0...","htmlSnippet":"Jul 25, 2014 <b>...</b> Check out the full-length <b>Tekken 7 trailer</b> straight from the Bandai Namco Games <br> Fighting Game Panel at San Diego Comic-Con 2014! Follow&nbsp;...","cacheId":"MmI6KIqGwI4J","formattedUrl":"https://www.youtube.com/watch?v=yTm6BV8RT9A","htmlFormattedUrl":"https://www.youtube.com/watch?v=yTm6BV8RT9A","pagemap":{"cse_thumbnail":[{"width":"300","height":"168","src":"https://encrypted-tbn1.gstatic.com/images?q=tbn:ANd9GcR-0L7ZLf24Vo2hFNsLE8awRPgmDlwznkynosWn71B-MX0u8-J4ZRuUgBnb"}],"imageobject":[{"url":"https://i.ytimg.com/vi/yTm6BV8RT9A/maxresdefault.jpg","width":"1280","height":"720"}],"person":[{"url":"http://www.youtube.com/user/NamcoBandaiGames"},{"url":"https://plus.google.com/117456562617165336918"}],"metatags":[{"title":"Tekken 7 - Full-Length SDCC 2014 Trailer","theme-color":"#e62117","og:site_name":"YouTube","og:url":"https://www.youtube.com/watch?v=yTm6BV8RT9A","og:title":"Tekken 7 - Full-Length SDCC 2014 Trailer","og:image":"https://i.ytimg.com/vi/yTm6BV8RT9A/maxresdefault.jpg","og:description":"Check out the full-length Tekken 7 trailer straight from the Bandai Namco Games Fighting Game Panel at San Diego Comic-Con 2014! Follow Katsuhiro Harada on T...","al:ios:app_store_id":"544007664","al:ios:app_name":"YouTube","al:ios:url":"vnd.youtube://www.youtube.com/watch?v=yTm6BV8RT9A&feature=applinks","al:android:url":"vnd.youtube://www.youtube.com/watch?v=yTm6BV8RT9A&feature=applinks","al:android:app_name":"YouTube","al:android:package":"com.google.android.youtube","al:web:url":"https://www.youtube.com/watch?v=yTm6BV8RT9A&feature=applinks","og:type":"video","og:video:url":"https://www.youtube.com/embed/yTm6BV8RT9A","og:video:secure_url":"https://www.youtube.com/embed/yTm6BV8RT9A","og:video:type":"text/html","og:video:width":"1280","og:video:height":"720","og:video:tag":"namco bandai games","fb:app_id":"87741124305","twitter:card":"player","twitter:site":"@youtube","twitter:url":"https://www.youtube.com/watch?v=yTm6BV8RT9A","twitter:title":"Tekken 7 - Full-Length SDCC 2014 Trailer","twitter:description":"Check out the full-length Tekken 7 trailer straight from the Bandai Namco Games Fighting Game Panel at San Diego Comic-Con 2014! Follow Katsuhiro Harada on T...","twitter:image":"https://i.ytimg.com/vi/yTm6BV8RT9A/maxresdefault.jpg","twitter:app:name:iphone":"YouTube","twitter:app:id:iphone":"544007664","twitter:app:name:ipad":"YouTube","twitter:app:id:ipad":"544007664","twitter:app:url:iphone":"vnd.youtube://www.youtube.com/watch?v=yTm6BV8RT9A&feature=applinks","twitter:app:url:ipad":"vnd.youtube://www.youtube.com/watch?v=yTm6BV8RT9A&feature=applinks"}],"videoobject":[{"url":"https://www.youtube.com/watch?v=yTm6BV8RT9A","name":"Tekken 7 - Full-Length SDCC 2014 Trailer","description":"Check out the full-length Tekken 7 trailer straight from the Bandai Namco Games Fighting Game Panel at San Diego Comic-Con 2014! Follow Katsuhiro Harada on T...","paid":"False","channelid":"UC_ntXHv-XdKCD7CPynVvnQw","videoid":"yTm6BV8RT9A","duration":"PT3M9S","unlisted":"False","thumbnailurl":"https://i.ytimg.com/vi/yTm6BV8RT9A/maxresdefault.jpg","embedurl":"https://www.youtube.com/embed/yTm6BV8RT9A","playertype":"HTML5 Flash","width":"1280","height":"720","isfamilyfriendly":"True","regionsallowed":"AD,AE,AF,AG,AI,AL,AM,AO,AQ,AR,AS,AT,AU,AW,AX,AZ,BA,BB,BD,BE,BF,BG,BH,BI,BJ,BL,BM,BN,BO,BQ,BR,BS,BT,BV,BW,BY,BZ,CA,CC,CD,CF,CG,CH,CI,CK,CL,CM,CN,CO,CR,CU,CV,CW,CX,CY,CZ,DE,DJ,DK,DM,DO,DZ,EC,EE,EG,EH...","interactioncount":"1444296","datepublished":"2014-07-25","genre":"Gaming"}],"cse_image":[{"src":"https://i.ytimg.com/vi/yTm6BV8RT9A/maxresdefault.jpg"}]}}]

JSON字符串太长了，它包含20个数据，所以我移到这里，http://codepad.org/Ib658BDD上面的JSON字符串示例只包含1个数据。

当我将JSON插入我的数据库时，我已经对JSON进行了编码

$json = file_get_contents("https://www.googleapis.com/customsearch/v1?q=Tekken%207&cx=XXX&key=XXX");
$json = json_decode($json, true);
$json = $json['items'];
mysql_query("INSERT INTO jsondata(jsondata) VALUES('".json_encode(preg_replace('/[\x00-\x1F\x80-\xFF]/', '', str_replace("'", "'", $json)))."')");

更新:看起来好像是因为JSON数据现在没有写好，所以我很怀疑要删除数据内部的“(引号)，例如

"snippet":"This video was taken from a facebook page, named "Dream Team Gaming"."

Answer 1

您的json数据是无效和不完整的。必须清除所有错误的反斜杠()并完成数据。如果json字符串无效，则json_decode命令返回null。您可以在http://json.parser.online.fr/上验证json数据。