{"id":245,"date":"2020-02-04T19:50:53","date_gmt":"2020-02-04T11:50:53","guid":{"rendered":"https:\/\/blog.cqdefxxx.com\/?p=245"},"modified":"2020-02-04T19:50:53","modified_gmt":"2020-02-04T11:50:53","slug":"number","status":"publish","type":"post","link":"https:\/\/blog.viter.top\/index.php\/2020\/02\/04\/number\/","title":{"rendered":"Number"},"content":{"rendered":"<pre class=\"pure-highlightjs\"><code class=\"\">&lt;!DOCTYPE html&gt;\n&lt;html&gt;\n\t&lt;head&gt;\n\t\t&lt;meta charset=\"UTF-8\"&gt;\n\t\t&lt;title&gt;&lt;\/title&gt;\n\t\t&lt;script type=\"text\/javascript\"&gt;\n\t\t\t\n\t\t\t\/*\n\t\t\t * \u5728JS\u4e2d\u6240\u6709\u7684\u6570\u503c\u90fd\u662fNumber\u7c7b\u578b\uff0c\n\t\t\t * \t\u5305\u62ec\u6574\u6570\u548c\u6d6e\u70b9\u6570\uff08\u5c0f\u6570\uff09\n\t\t\t * \n\t\t\t * JS\u4e2d\u53ef\u4ee5\u8868\u793a\u7684\u6570\u5b57\u7684\u6700\u5927\u503c\n\t\t\t * \tNumber.MAX_VALUE\n\t\t\t * \t\t1.7976931348623157e+308\n\t\t\t * \n\t\t\t * \tNumber.MIN_VALUE \u5927\u4e8e0\u7684\u6700\u5c0f\u503c\n\t\t\t * \t\t5e-324\n\t\t\t * \n\t\t\t *  \u5982\u679c\u4f7f\u7528Number\u8868\u793a\u7684\u6570\u5b57\u8d85\u8fc7\u4e86\u6700\u5927\u503c\uff0c\u5219\u4f1a\u8fd4\u56de\u4e00\u4e2a\n\t\t\t * \t\tInfinity \u8868\u793a\u6b63\u65e0\u7a77\n\t\t\t * \t\t-Infinity \u8868\u793a\u8d1f\u65e0\u7a77\n\t\t\t * \t\t\u4f7f\u7528typeof\u68c0\u67e5Infinity\u4e5f\u4f1a\u8fd4\u56denumber\n\t\t\t *  NaN \u662f\u4e00\u4e2a\u7279\u6b8a\u7684\u6570\u5b57\uff0c\u8868\u793aNot A Number\n\t\t\t * \t\t\u4f7f\u7528typeof\u68c0\u67e5\u4e00\u4e2aNaN\u4e5f\u4f1a\u8fd4\u56denumber\n\t\t\t *\/\n\t\t\t\/\/\u6570\u5b57123\n\t\t\tvar a = 123;\n\t\t\t\/\/\u5b57\u7b26\u4e32123\n\t\t\tvar b = \"123\";\n\t\t\t\/*\n\t\t\t \t\u53ef\u4ee5\u4f7f\u7528\u4e00\u4e2a\u8fd0\u7b97\u7b26 typeof\n\t\t\t \t\t\u6765\u68c0\u67e5\u4e00\u4e2a\u53d8\u91cf\u7684\u7c7b\u578b\n\t\t\t \t\u8bed\u6cd5\uff1atypeof \u53d8\u91cf\t\n\t\t\t \t\u68c0\u67e5\u5b57\u7b26\u4e32\u65f6\uff0c\u4f1a\u8fd4\u56destring\n\t\t\t \t\u68c0\u67e5\u6570\u503c\u65f6\uff0c\u4f1a\u8fd4\u56denumber\n\t\t\t * *\/\n\t\t\t\/\/console.log(typeof b);\n\t\t\t\n\t\t\ta = -Number.MAX_VALUE * Number.MAX_VALUE;\n\t\t\t\n\t\t\ta = \"abc\" * \"bcd\";\n\t\t\t\n\t\t\ta = NaN;\n\t\t\t\n\t\t\t\/\/console.log(typeof a);\n\t\t\t\n\t\t\ta = Number.MIN_VALUE;\n\t\t\t\n\t\t\t\/\/console.log(a);\n\t\t\t\n\t\t\t\/*\n\t\t\t * \u5728JS\u4e2d\u6574\u6570\u7684\u8fd0\u7b97\u57fa\u672c\u53ef\u4ee5\u4fdd\u8bc1\u7cbe\u786e\n\t\t\t *\/\n\t\t\tvar c = 1865789 + 7654321;\n\t\t\t\n\t\t\t\/*\n\t\t\t * \u5982\u679c\u4f7f\u7528JS\u8fdb\u884c\u6d6e\u70b9\u8fd0\u7b97\uff0c\u53ef\u80fd\u5f97\u5230\u4e00\u4e2a\u4e0d\u7cbe\u786e\u7684\u7ed3\u679c\n\t\t\t * \t\u6240\u4ee5\u5343\u4e07\u4e0d\u8981\u4f7f\u7528JS\u8fdb\u884c\u5bf9\u7cbe\u786e\u5ea6\u8981\u6c42\u6bd4\u8f83\u9ad8\u7684\u8fd0\u7b97\t\n\t\t\t *\/\n\t\t\tvar c = 0.1 + 0.2;\n\t\t\t\n\t\t\tconsole.log(c);\n\t\t\t\n\t\t\t\n\t\t&lt;\/script&gt;\n\t&lt;\/head&gt;\n\t&lt;body&gt;\n\t&lt;\/body&gt;\n&lt;\/html&gt;\n<\/code><\/pre>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>&lt;!DOCTYPE html&gt; &lt;html&gt; &lt;head&gt; &lt;meta charset= &#8230;<\/p>","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[],"tags":[4],"_links":{"self":[{"href":"https:\/\/blog.viter.top\/index.php\/wp-json\/wp\/v2\/posts\/245"}],"collection":[{"href":"https:\/\/blog.viter.top\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.viter.top\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.viter.top\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.viter.top\/index.php\/wp-json\/wp\/v2\/comments?post=245"}],"version-history":[{"count":0,"href":"https:\/\/blog.viter.top\/index.php\/wp-json\/wp\/v2\/posts\/245\/revisions"}],"wp:attachment":[{"href":"https:\/\/blog.viter.top\/index.php\/wp-json\/wp\/v2\/media?parent=245"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.viter.top\/index.php\/wp-json\/wp\/v2\/categories?post=245"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.viter.top\/index.php\/wp-json\/wp\/v2\/tags?post=245"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}