{"id":319,"date":"2016-08-02T06:58:28","date_gmt":"2016-08-01T21:58:28","guid":{"rendered":"https:\/\/blog.srytk.com\/aquei\/?p=319"},"modified":"2016-08-02T06:58:28","modified_gmt":"2016-08-01T21:58:28","slug":"img%e8%a6%81%e7%b4%a0%e3%81%aesizes%e5%b1%9e%e6%80%a7%e3%81%ae%e3%82%bd%e3%83%bc%e3%82%b9%e3%82%b5%e3%82%a4%e3%82%ba%e5%80%a4%e3%81%ab%e7%9b%b8%e5%af%be%e7%9a%84%e3%81%aa%e5%8d%98%e4%bd%8d%e3%82%92","status":"publish","type":"post","link":"https:\/\/blog.srytk.com\/aquei\/319.html","title":{"rendered":"img\u8981\u7d20\u306esizes\u5c5e\u6027\u306e\u30bd\u30fc\u30b9\u30b5\u30a4\u30ba\u5024\u306b\u76f8\u5bfe\u7684\u306a\u5358\u4f4d\u3092\u4f7f\u3063\u3066\u3082\u30d9\u30fc\u30b9\u9577\u306f\u56fa\u5b9a"},"content":{"rendered":"
\u00a9 Benjamin Deutsch<\/a> – “measure” – \u30af\u30ea\u30a8\u30a4\u30c6\u30a3\u30d6\u30fb\u30b3\u30e2\u30f3\u30ba: \u8868\u793a<\/a><\/figcaption><\/figure>\n

CSS\u306e\u9577\u3055\u306e\u5358\u4f4d\u306bem\u3084rem\u304c\u3042\u308b\u3002em\u306ffont-size\u306e\u8a08\u7b97\u5024\u3092\u5143\u306b\u3057\u305f\u76f8\u5bfe\u7684\u306a\u9577\u3055\u3002\u3067rem\u306froot\u306eem\u3001\u3064\u307e\u308ahtml\u8981\u7d20\u306efont-size<\/a>\u3002<\/p>\n

em<\/code>\u3000\u5f53\u8a72\u8981\u7d20\u306e font-size \u306e\u8a08\u7b97\u5024\u3092\u8868\u3057\u307e\u3059\u3002font-size \u30d7\u30ed\u30d1\u30c6\u30a3\u81ea\u8eab\u306b\u4f7f\u308f\u308c\u308b\u3068\u3001\u8981\u7d20\u306e\u7d99\u627f\u3055\u308c\u305f\u30d5\u30a9\u30f3\u30c8\u30b5\u30a4\u30ba\u306e\u5024\u3092\u8868\u3057\u307e\u3059\u3002<\/p>\n

\u4e2d\u7565<\/p>\n

rem<\/code>\u3000\u30eb\u30fc\u30c8\u8981\u7d20\u306e font-size<\/code> (\u4f8b\u3048\u3070\u3001html<\/code> \u8981\u7d20\u306e font-size<\/code>) \u3067\u3059\u3002\u30eb\u30fc\u30c8\u8981\u7d20\u3067\u4f7f\u3046\u3068\u521d\u671f\u5024\u3092\u8868\u3057\u307e\u3059\u3002<\/p><\/blockquote>\n

css\u306e\u5358\u4f4d\u3060\u304b\u3089\u30b9\u30bf\u30a4\u30eb\u30b7\u30fc\u30c8\u306b\u8a18\u8ff0\u3059\u308b\u3053\u3068\u304c\u591a\u3044\u3051\u3069\u3001<img>\u306esizes\u5c5e\u6027<\/a>\u306b\u30e1\u30c7\u30a3\u30a2\u30af\u30a8\u30ea\u3084\u30bd\u30fc\u30b9\u30b5\u30a4\u30ba\u5024\u3068\u3057\u3066\u66f8\u304f\u3053\u3068\u3082\u3042\u308b\u3002\u3067\u3001\u5148\u65e5img\u8981\u7d20\u306esizes\u5c5e\u6027\u3092\u8abf\u3079\u3066\u3044\u308b\u6642\u306b\u3001\u3075\u3068\u7591\u554f\u304c\u6d6e\u304b\u3093\u3060\u3002<\/p>\n

<\/p>\n

CSSOM\u306e\u69cb\u7bc9\u304c\u5b8c\u4e86\u3059\u308b\u307e\u3067\u30ea\u30af\u30a8\u30b9\u30c8\u306f\u30d6\u30ed\u30c3\u30af\u3055\u308c\u308b\uff1f<\/h2>\n

em\u3084rem\u306a\u3069\u306f\u76f8\u5bfe\u7684\u306a\u9577\u3055\u306a\u306e\u3067\u3001CSSOM\u306e\u69cb\u7bc9\u304c\u5b8c\u4e86\u3059\u308b\u307e\u3067\u7d76\u5bfe\u7684\u306a\u9577\u3055\u304c\u308f\u304b\u3089\u306a\u3044\u306f\u305a\u3002\u3068\u3044\u3046\u3053\u3068\u306f\u3001\u30d6\u30e9\u30a6\u30b6\u304c\u6700\u9069\u306a\u753b\u50cf\u3092\u30ea\u30af\u30a8\u30b9\u30c8\u3059\u308b\u305f\u3081\u306bCSSOM\u306e\u69cb\u7bc9\u306e\u5b8c\u4e86\u307e\u3067\u30d5\u30a1\u30a4\u30eb\u306e\u30c0\u30a6\u30f3\u30ed\u30fc\u30c9\u304c\u958b\u59cb\u3055\u308c\u306a\u3044\u306e\u3060\u308d\u3046\u304b\u3002CSS\u3068\u753b\u50cf\u306f\u30d1\u30e9\u30ec\u30eb\u306b\u30ea\u30af\u30a8\u30b9\u30c8\u3067\u304d\u306a\u3044\uff1f\uff1f\uff1f\u3046\u30fc\u3093\u3001\u3061\u3087\u3063\u3068\u8abf\u3079\u3066\u307f\u3088\u3046\u3002<\/p>\n

<img sizes=\"12.5em\" srcset=\"https:\/\/placehold.it\/200x100 200w, https:\/\/placehold.it\/400x200 400w, https:\/\/placehold.it\/600x300 600w\">\r\n<\/code><\/pre>\n
\u3053\u3093\u306aimg\u8981\u7d20\u304c\u3042\u3063\u305f\u3068\u3057\u3066\u30011em=16px\u306e\u5834\u5408\u300112.5em\u306f200px(12.5*16=200)\u3060\u304b\u3089\u3001devicePixelRatio\u304c1\u306e\u5834\u5408<\/p>\n
https:\/\/placehold.it\/200×100<\/figcaption><\/figure>\n
\u304c\u8868\u793a\u3055\u308c\u308b\u306f\u305a\u3002\u3058\u3083\u3042\u3001\u3053\u3093\u306aimg\u8981\u7d20\u3069\u3046\u3060\u308d\u3046\u3002<\/p>\n
<img style=\"font-size:32px;\" sizes=\"12.5em\" srcset=\"https:\/\/placehold.it\/200x100 200w, https:\/\/placehold.it\/400x200 400w, https:\/\/placehold.it\/600x300 600w\"><\/code><\/pre>\n
\u3053\u306eimg\u306f1em=32px\u3060\u304b\u3089\u300132*12.5 = 400\u3067\u3001<\/p>\n
https:\/\/placehold.it\/400×200<\/figcaption><\/figure>\n
\u304c\u8868\u793a\u3055\u308c\u308b\uff1f\u3044\u3084\u3001\u8a66\u3057\u3066\u307f\u305f\u3051\u3069\u3001\u305d\u3093\u306a\u4e8b\u306f\u7121\u304b\u3063\u305f\u3002\u3053\u306eimg\u8981\u7d20\u3082<\/p>\n
https:\/\/placehold.it\/200×100<\/figcaption><\/figure>\n
\u304c\u8868\u793a\u3055\u308c\u305f\u3002\u3053\u308c\u306frem\u5358\u4f4d\u3067\u3082\u540c\u3058\u3060\u3063\u305f\u3002<\/p>\n
\u3068\u3069\u306e\u3064\u307e\u308a\u3001em\u3084rem\u306a\u3069\u76f8\u5bfe\u7684\u306a\u5358\u4f4d\u3067\u3082\u3001\u30d9\u30fc\u30b9\u3068\u306a\u308b\u7d76\u5bfe\u7684\u306a\u9577\u3055\u306f\u3001\u30d6\u30e9\u30a6\u30b6\u306e\u30c7\u30d5\u30a9\u30eb\u30c8\u5024\u304c\u5229\u7528\u3055\u308c\u308b\u3088\u3046\u3060\u3002\u3053\u308c\u306f\u5c11\u3057\u6df7\u4e71\u3059\u308b\u3002\u4f8b\u3048\u3070\u3001<\/p>\n
<div style=\"font-size:32px;width:12.5em\">400px<\/div><\/code><\/pre>\n
\u306f\u6a2a\u5e45400px\u306ediv\u304c\u8868\u793a\u3055\u308c\u308b\u3001200px\u3067\u306f\u306a\u3044\u3002sizes\u5c5e\u6027\u306fCSSOM\u3092\u7121\u8996\u3059\u308b\u3088\u3046\u3060\u3002<\/p>\n
\u305d\u3046\u3044\u3046\u308f\u3051\u3067\u3001\u7d50\u5c40\u3001\u6700\u521d\u306e\u7591\u554f(CSSOM\u306e\u69cb\u7bc9\u304c\u5b8c\u4e86\u3059\u308b\u307e\u3067\u753b\u50cf\u306e\u30ea\u30af\u30a8\u30b9\u30c8\u306f\u30d6\u30ed\u30c3\u30af\u3055\u308c\u308b\uff1f)\u306f\u675e\u6182\u306b\u7d42\u308f\u3063\u305f\u3002\u307e\u3042\u3001\u305d\u308c\u3067\u3082\u7d1b\u3089\u308f\u3057\u3044\u306e\u3067\u3001sizes\u5c5e\u6027\u306b\u306f\u7d76\u5bfe\u7684\u306a\u9577\u3055\u3092\u6307\u5b9a\u3059\u308b\u306e\u304c\u826f\u3055\u305d\u3046\u3060\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
CSS\u306e\u9577\u3055\u306e\u5358\u4f4d\u306bem\u3084rem\u304c\u3042\u308b\u3002em\u306ffont-size\u306e\u8a08\u7b97\u5024\u3092\u5143\u306b\u3057\u305f\u76f8\u5bfe\u7684\u306a\u9577\u3055\u3002\u3067rem\u306froot\u306eem\u3001\u3064\u307e\u308ahtml\u8981\u7d20\u306efont-size\u3002 em\u3000\u5f53\u8a72\u8981\u7d20\u306e font-size \u306e\u8a08\u7b97\u5024\u3092\u8868\u3057\u307e\u3059 […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"activitypub_content_warning":"","activitypub_content_visibility":"local","activitypub_max_image_attachments":5,"footnotes":""},"categories":[2],"tags":[21],"class_list":["post-319","post","type-post","status-publish","format-standard","hentry","category-tech","tag-css"],"_links":{"self":[{"href":"https:\/\/blog.srytk.com\/aquei\/wp-json\/wp\/v2\/posts\/319","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blog.srytk.com\/aquei\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.srytk.com\/aquei\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.srytk.com\/aquei\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.srytk.com\/aquei\/wp-json\/wp\/v2\/comments?post=319"}],"version-history":[{"count":1,"href":"https:\/\/blog.srytk.com\/aquei\/wp-json\/wp\/v2\/posts\/319\/revisions"}],"predecessor-version":[{"id":320,"href":"https:\/\/blog.srytk.com\/aquei\/wp-json\/wp\/v2\/posts\/319\/revisions\/320"}],"wp:attachment":[{"href":"https:\/\/blog.srytk.com\/aquei\/wp-json\/wp\/v2\/media?parent=319"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.srytk.com\/aquei\/wp-json\/wp\/v2\/categories?post=319"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.srytk.com\/aquei\/wp-json\/wp\/v2\/tags?post=319"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}