{"id":8102,"date":"2020-07-01T17:43:07","date_gmt":"2020-07-01T09:43:07","guid":{"rendered":"https:\/\/sdeno.com\/?p=8102"},"modified":"2020-07-01T17:43:36","modified_gmt":"2020-07-01T09:43:36","slug":"js%e4%b8%ad%e6%9c%89onload%e5%9b%9e%e8%b0%83%e4%ba%8b%e4%bb%b6%e9%9c%80%e8%a6%81return%e8%bf%94%e5%9b%9e%e5%80%bc","status":"publish","type":"post","link":"https:\/\/sdeno.com\/?p=8102","title":{"rendered":"js\u4e2d\u5728onload\u56de\u8c03\u4e8b\u4ef6\u9700\u8981return\u8fd4\u56de\u503c"},"content":{"rendered":"<pre>function test(url){\r\n var str=undefined;\r\n var img =new Image()\r\n img.src=url\r\n img.onload=function(){\r\n   str=img\r\n }\r\n return str\r\n}<\/pre>\n<p>\u4e8b\u5b9e\u4e0atest()\u76f4\u63a5\u5c31\u8fd4\u56de\u4e86undefined\uff0c\u8bf4\u660eonload\u8981\u7b49\u5f85img\u8d44\u6e90\u90fd\u52a0\u518d\u5b8c\u6210\u4e86\u624d\u80fd\u6267\u884c\uff0c\u4e0d\u80fd\u4fdd\u8bc1\u540c\u6b65\u6267\u884c<\/p>\n<p>&nbsp;<\/p>\n<p><span style=\"color: #ff0000;\">\u89e3\u51b3\u65b9\u6cd5\u4e00\uff1a<\/span><\/p>\n<p>\u57fa\u4e8ejQuery\u517c\u5bb9\u6027\u597d<\/p>\n<pre>function test(url){\r\n    var img =new Image();\r\n    img.title='xxxx';\r\n    img.src=url;\r\n    var deferred = $.Deferred();\r\n    img.onload=function () {\r\n       deferred.resolve(img);\r\n    }\r\n    return deferred.promise();\r\n}\r\n\r\n\/\/\u56fe\u7247\u5730\u5740\u52a0\u8f7d\u6709\u5ef6\u8fdf\r\ntest('http:\/\/lorempixel.com\/100\/100?0.6412381180562079').then((res)=&gt;{\r\n    console.log(res)  \/\/&lt;img title=\"xxxx\" src=\"http:\/\/lorempixel.com\/100\/100?0.6412381180562079\"&gt;\r\n})<\/pre>\n<p>&nbsp;<\/p>\n<p><span style=\"color: #ff0000;\">\u89e3\u51b3\u65b9\u6cd5\u4e8c\uff1a<\/span><\/p>\n<p>\u4e0d\u9700\u8981\u4efb\u4f55\u7b2c\u4e09\u65b9\u63d2\u4ef6<\/p>\n<pre>function test(url){\r\n    return new Promise(function (a,b) {\r\n            var img =new Image();\r\n            img.title='xxxx';\r\n            img.src=url;\r\n            img.onload=function () {\r\n                a(img)\r\n            }\r\n    })\r\n}\r\n\r\ntest('http:\/\/lorempixel.com\/100\/100?0.6412381180562079').then((res)=&gt;{\r\n    console.log(res)\r\n})<\/pre>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>function test(url){ var str=undefined; var img =new Ima [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[11],"tags":[],"class_list":["post-8102","post","type-post","status-publish","format-standard","hentry","category-11"],"_links":{"self":[{"href":"https:\/\/sdeno.com\/index.php?rest_route=\/wp\/v2\/posts\/8102","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/sdeno.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/sdeno.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/sdeno.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/sdeno.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=8102"}],"version-history":[{"count":0,"href":"https:\/\/sdeno.com\/index.php?rest_route=\/wp\/v2\/posts\/8102\/revisions"}],"wp:attachment":[{"href":"https:\/\/sdeno.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=8102"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/sdeno.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=8102"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/sdeno.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=8102"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}