ã¯ããã« éããã³ãã¨ã³ã¸ãã¢ã®æ¹ã ã«ã¨ã£ã¦ãJavaScriptã¯ç¬ç¹ã§ã¨ã£ã¤ãã«ããè¨èªã ã¨æãã¾ããæè¿Reactãæµè¡ã£ã¦ãã¾ãããJavaScriptãåãããªãã¦æãåºããªã人ãçµæ§ããã®ã§ã¯ãªãã§ããããã ãã®è¨äºã§ã¯ãæ®æ®µJavaScriptããã¾ã触ããªã人ã対象ã«ãã¢ãã³ãªã©ã¤ãã©ãªçããããã®ã«å¿ è¦ãªJavaScriptã®è¨è¨ã»ææ³ã»ææ³ã解説ãã¾ããé¢æ°ãªãã¸ã§ã¯ããé¢æ°ã¹ã³ã¼ããthisã«é¢ãã¦ã¯ç¥ã£ã¦ãããªãã¨ES2015ã§ã確å®ã«èºãã®ã§ãããã¦æ¯éãé«ããã¦èª¬æãã¦ãã¾ãã â»å³å¯ã§ã¯ãªãç®æãããããããã¾ããããã容赦ãã ããã JavaScriptã¨ã¯ æ´å² 1995å¹´ã«Netscape社ã«ããéçºãããå½ææµè¡ãã¦ããJavaã®åæ¨ã使ã£ã¦ãJavaScriptãã¨åä»ãããã¾ãããææ³ã¯æ¯è¼çä¼¼ã¦ãã¾ãããJavaã¨JavaScriptã¯ã¤ã³ãã¨
Winã§ã¯åºæ¬çã«ãã©ã³ãã¬ã³ããªã³ã°ãCSSã§å¶å¾¡ãããã¨ã¯åºæ¥ã¾ãããã¾ããã¹ãã¼ããã©ã³ã®ãã©ã¦ã¶ãã»ã¨ãã©å¶å¾¡ã§ãããåºæ¬çã«ã°ã¬ã¼ã¹ã±ã¼ã«ã§è¡¨ç¤ºããããã¨ãå¤ãããã§ããã Macã§ã¯Safariã®ã¿ãã°ã¬ã¼ã¹ã±ã¼ã«ã§ããããããåå ã§ãSafariã§æåãç´°ãè¦ãã¦ãã¾ããç¾è±¡ãèµ·ãã£ã¦ãã¾ãã ããã¤ã¹ã®dpiã«ããè¦ãæ¹ ãã®ã¾ã¾åãã©ã¦ã¶ã§ã¢ã³ãã¨ã¤ãªã¢ã¹ãæããè¨å®ãã¦ãè¯ãã®ã§ããã1x, 2xã®è§£å度ã«ããè¦ãæ¹ãè¦ã¦ããã¾ãããã(ä»åã¯Thunderbolt Display = 109ppi, MBP Retina Display = 220ppiã§æ¤è¨¼ã»æ¯è¼ãå®éã«è¡¨ç¤ºããç»é¢ãã¹ããã®ã«ã¡ã©ã§å å·¥ãç¡ãããã«ãã¦æ®ãã¾ããã) 109ppi(Thunderbolt Display) 220ppi(MBP Retina Display) 以ä¸ã®ãã¨ããããã¾ã
ãµã¼ãã¹çµäºã®ãç¥ãã ãã¤ãYahoo! JAPANã®ãµã¼ãã¹ããå©ç¨ããã ãèª ã«ãããã¨ããããã¾ãã ã客æ§ãã¢ã¯ã»ã¹ããããµã¼ãã¹ã¯æ¬æ¥ã¾ã§ã«ãµã¼ãã¹ãçµäºãããã¾ããã ä»å¾ã¨ãYahoo! JAPANã®ãµã¼ãã¹ããæ顧ãã ããã¾ãããããããããé¡ããããã¾ãã
ä¸è¡ã§é ¼ã ã³ã³ãã¤ã©ãæãä¸ã®æé©åãããããã«ãªã£ãããnullå®å ¨ãªãã¨æããã ä¸è¡ã§çµãã£ã¡ãã£ãã æ¬æ æè¿ããã¤ãã¿ã¼ãè¦ã¦ããã¨ãããã°ã©ãã®éã§nullå®å ¨ã¨ããè¨èãããºã£ã¦ãã¾ãããç§ã次ã®ãããªã¨ã³ããªã楽ããçºãã¦ãã訳ã§ãï¼ nullå®å ¨ã§ãªãè¨èªã¯ããã¯ãã¬ã¬ã·ã¼è¨èªã nullå®å ¨ã¯ããããã ã£ã¦ãåå®å ¨ã¯ãããã nullå®å ¨ã誤解ãã¦ãã人éã¸ã®ã¡ãã»ã¼ã¸ ãã¦ãããªä¸ãå°ãã ãç§ã®å¿ã«çã¾ã£ãã¨ã³ããªãããã§ãï¼ nullå®å ¨ãªè¨èªã¯ãæ¬å½ã«ã¼ãã³ã¹ãã ãããèªãã§ãç§ãã¾ãç´æçã«æã£ãã®ã¯ãããããã¯ãnullå®å ¨ã®ãªãè¨èªã¯ãã¡ãããããªãã¨ãããã¨ã§ãããããæ¸ãã¨ããã®ã¨ã³ããªã®å 容ãå¦å®ãã¦ãã¨èª¤è§£ãããããããã¾ããããå ¨ããããªãã¨ã¯ããã¾ããããã®ã¨ã³ããªã®çè ãããnullå®å ¨ã®æç¨æ§ãå¦å®ãã¦ããããã§ã¯ãªãã§ãããç§ãå¤ãã¿
æååãªãã©ã« HTMLãå«ãæååãçæããéã«ä¾¿å©ãªãããå²ãæã¯ã·ã³ã°ã«ã¯ã©ã¼ã'hoge'ããã ã»ãã³ãã³ æ«å°¾ã«ã»ãã³ãã³ãã¤ããªãã¦ã解éãã¦ããããããã°ãçãå¯è½æ§ãããã®ã§ã»ãã³ãã³ã¯ã¤ããããã«ç¿æ £åãã ES6ã®classè¨æ³ã®ã¡ã½ããæ«å°¾ã«ã¯ã»ãã³ãã³ä¸è¦ åå¤æ¯è¼ åºæ¬çã«===ãã¤ããã==ã ã¨å¯å®¹éãã解éã®ããããã°ãçããã¨ãããã ç絡è©ä¾¡ hogeFuncã®å¼æ°ã«trueç¸å½ã®å¤ãå ¥ã£ã¦ããå ´åã ||ã®å³å´ã¯èªã¾ããªãã hogeFuncã®å¼æ°ã«falseç¸å½ã®å¤ãå ¥ã£ã¦ããå ´åã ï¼false, null, undefined, NaN, "", 0ï¼ ||ã®å³å´ãèªã¿ã«ããã function hogeFunc(e){ e || console.log('piyo'); } hogeFunc(1); // ä½ãåºåãããªããããç絡è©ä¾¡ããªãã
getElementByIdã¨getElementsByNameã£ã¦ãã使ãæ¹ãééãã¾ããï¼ç§ã ãããã§ãããï¼ ã¨ãããã¨ã§ãåºæ¬ä¸ã®åºæ¬ã®getElementByIdã¨getElementsByNameã®ä½¿ãæ¹ãã¾ã¨ãã¦ã¿ã¾ãã â»ãgetElementByNameãã§ã¯ç¡ããgetElementsByNameãã ã£ã¦ã¨ãããã¡ãã£ã¨éè¦ã§ãã getElementByIdã®åºæ¬çãªä½¿ãæ¹ getElementByIdã®åºæ¬çãªä½¿ãæ¹ã¯ä»¥ä¸ã®éãã§ãã â document.getElementById(id) (D1/e5/N6/O6) id å±æ§ã§æå®ããååã§è¦ç´ ãåç §ãã¾ãã oElement = document.getElementById("id1"); ã¨ã»ã»ã®JavaScriptãªãã¡ã¬ã³ã¹ - ããã¥ã¡ã³ããªãã¸ã§ã¯ãã¢ãã«ï¼DOMï¼ ãid å±æ§ã§æå®ããååã§
ãæè¡çè² åµã ããã®ãã¼ã ã§æè¡ããã¼ã¸ã¡ã³ããã¦ã¿ããã®å ¬éè³æãç´ æ´ãããã®ã§ãªã³ã¯ãã¦ããã ãåèã akipiiããã®ãã¤ã¼ã: "ãããè¯ãè³æãRT @yassan168: #kichijojipm çºè¡¨è³æupãã¾ããã誰ãã®å½¹ã«ãã¦ã°è¯ãã®ã ãã©ãconnpassã«ãUPãã¦ãã¾ããï¼æè¡çè² åµã ããã®ãã¼ã ã§æè¡ããã¼ã¸ã¡ã³ããã¦ã¿ã https://t.co/3R25aUnI4S" åä»»ã®ä»äºãå¼ãç¶ãããããä¸è¨ã®åé¡ããã£ããããã æè¡çè² åµè¾¼ã¿ã§å¼ãç¶ãã§ãã¾ã£ããã¨ããä¾ã¯ãæ¬å½ã«ããããã (å¼ç¨éå§) ï¼å¹´åã®ç¶æ ã»ãã¹ã¦ãã¡ã¼ã«ãã¼ã¹ ã»ããã¥ã¡ã³ãã¯ã»ã¼ç¡ã ã»æå¼·ã®å±äººåãå人ã®ãã¯ã¼ã§ä¹ãåã ã»æè¡ã«é¢å¿ãç¡ã誰ãè¡åããªã ã»æ«å®ã¹ã¯ãªãããä»ãå æ°ã«æ¬çªç¨¼åä¸ ã»ã½ã¼ã¹ã«ã¯ãã»ã¼ã³ã¡ã³ãç¡ã ã»hoge.pl.(æ¥ä») å½¢å¼ã®ã½ã¼ã¹ç®¡ç
ä»ã¾ã§ããã¨ãã¦ã¡ãã£ã¨ã ãããã°ã«ç»å ´ãã¦ãã夫ã§ãããæ¬äººãããã°ãå§ãããã¨ã§ãããä»æ¥ã¯å¤«ã®ãã¨ãæ¸ãã¦ã¿ããã¨æãã¾ãã 夫ã¯ITæè¡è ã§ãããçé¢ç®ã§å強家ã§ãã¶ãã¡ãã£ã¨å¤ãã£ã人ã§ããã¡ãªã¿ã«ç§ã¯å ¸åçãªæç³»ã§æ°åãæ©æ¢°ãè¦æãåå¼·ãè¦æã§ãï¼ç¬ï¼ matome.naver.jp âããããã®ããããã§ããããããããã£ãã®ã§æã家ã®å¤«ã®å ´åãæ¸ãã¦ã¿ããã¨æãã¾ãã æ®éã ã¨æã£ã¦ãããå®ã¯éã£ã¦ããã㨠ï¼ï¼Apple製åã大好ãã§æ°è£½åã®çºè¡¨ã®æ¥ã¯å¹³æ¥ã§ãå¤æ´ããããã ï¼ï¼iPhoneã¯æ°ããæ©ç¨®ãåºã度ã«æ©ç¨®å¤æ´ã妻ã¯å¤«ã®ãä¸ããã使ãã ï¼ï¼iPadãåãã ï¼ï¼å¤«ãã¡ã³ãããããã¨ããçç±ã§å¦»ã®ãã½ã³ã³ãMacBookAirã ï¼ï¼ã§ãExcelã»Wordã¯å¦»ã®ã»ããå¾æã ï¼ï¼æã ã³ã£ãããããããé«ãã¦è¾æ¸ã¿ããã«ååãæ¬ï¼æè¡æ¸ï¼ãè²·ãã ï¼ï¼å¤«ã®ä½æ¥ã
ãªãªã¼ã¹ãé害æ å ±ãªã©ã®ãµã¼ãã¹ã®ãç¥ãã
ææ°ã®äººæ°ã¨ã³ããªã¼ã®é ä¿¡
å¦çãå®è¡ä¸ã§ã
j次ã®ããã¯ãã¼ã¯
kåã®ããã¯ãã¼ã¯
lãã¨ã§èªã
eã³ã¡ã³ãä¸è¦§ãéã
oãã¼ã¸ãéã
{{#tags}}- {{label}}
{{/tags}}