{"id":599,"date":"2018-02-15T14:49:47","date_gmt":"2018-02-15T06:49:47","guid":{"rendered":"http:\/\/zouyang1230.com\/blog\/?p=599"},"modified":"2020-10-28T22:46:47","modified_gmt":"2020-10-28T14:46:47","slug":"js%e6%8a%80%e5%b7%a7%ef%bc%9a%e5%8f%98%e9%87%8f%e7%89%b9%e6%80%a7%e4%b9%8bundefined","status":"publish","type":"post","link":"http:\/\/www.imzouyang.com\/blog\/archives\/599.html","title":{"rendered":"js\u6280\u5de7\uff1a\u907f\u514d\u83b7\u53d6\u53d8\u91cf\u6216\u5c5e\u6027\u62a5\u9519"},"content":{"rendered":"<p>\u4e00\u3001<\/p>\n<h4>1\u3001\u5148\u770b\u4e00\u4e2a\u793a\u4f8b1\uff1a<\/h4>\n<pre><code class=\"javascript\">\n\nvar a = 'abc';  \n\nalert(window.a)   \/\/abc  \nalert(a) \/\/abc\n\nalert(window.b)   \/\/undefined\nalert(b) \/\/\u62a5\u9519\n\n<\/code><\/pre>\n<p>\u4ece\u4e0a\u4f8b\u53ef\u4ee5\u770b\u51fa\uff0c\u5982\u679c\u4e00\u4e2a\u53d8\u91cfb\u6ca1\u6709\u58f0\u660e\uff0calert(window.b)  \u8fd4\u56deundefined\uff0calert(b) \u4f1a\u76f4\u63a5\u62a5\u9519\u3002<\/p>\n<p>&nbsp;<\/p>\n<h4>2\u3001\u77e5\u8bc6\u70b91\uff1a<\/h4>\n<p>\u4f7f\u7528\u4e00\u4e2a\u4e0d\u5b58\u5728\u7684\u53d8\u91cf\uff0c\u4f1a\u62a5\u9519\uff1b<br \/>\n\u4f7f\u7528\u4e00\u4e2a\u4e0d\u5b58\u5728\u7684\u5c5e\u6027\uff0c\u8fd4\u56deundefined\u3002\u5f53\u6211\u4eec\u628a\u67d0\u4e2a\u53d8\u91cf\u5f53\u4f5c\u4e00\u4e2a\u5c5e\u6027\u6765\u83b7\u53d6\u65f6\uff0c\u5373\u4fbf\u8be5\u53d8\u91cf\u4e0d\u5b58\u5728\uff0c\u4e5f\u4e0d\u4f1a\u5bfc\u81f4\u7a0b\u5e8f\u62a5\u9519\u3002<\/p>\n<p>&nbsp;<\/p>\n<h4>3\u3001\u5e94\u75281\uff1a<\/h4>\n<p>\u5728\u8fdb\u884cif\u6761\u4ef6\u5224\u65ad\u65f6\uff0c\u5982\u679c\u6761\u4ef6\u503c\u5982\u679c\u53ef\u80fd\u662f\u4e00\u4e2a\u4e0d\u5b58\u5728\u7684\u53d8\u91cf\u503c\uff0c\u5b58\u5728\u62a5\u9519\u98ce\u9669\u3002<br \/>\n\u6b64\u65f6\u53ef\u7528\u5bf9\u8c61\u5c5e\u6027\u7684\u65b9\u5f0f\u6765\u8c03\u7528\u8be5\u53d8\u91cf\u3002<\/p>\n<pre><code class=\"javascript\">\n\/\/JQ 2.0.3\u6e90\u7801\uff1a 354\u884c\nif ( window.$ === jQuery ) {\n    window.$ = _$;\n}\n<\/code><\/pre>\n<p>&nbsp;<\/p>\n<p>\u4e8c\u3001<\/p>\n<h4>1\u3001\u5148\u770b\u4e00\u4e2a\u793a\u4f8b2\uff1a<\/h4>\n<pre><code class=\"javascript\">\n\nvar sTitle = book.subtitle; 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|| \u8fd9\u7c7b\u8fd0\u7b97\u7b26\u5728\u8d4b\u503c\u65f6\u7684\u7528\u6cd5\u7684\uff08JQ\u6e90\u7801\u91cc\u5927\u91cf\u4f7f\u7528\u6b64\u7c7b\u4e66\u5199\u683c\u5f0f\uff09\uff0c<a href=\"http:\/\/zouyang1230.com\/blog\/archives\/726\">\u70b9\u6b64\u524d\u5f80<\/a>\u3002<br \/>\n&nbsp;<\/p>\n<p>\u4ee5\u4e0a\uff0c\u611f\u8c22\u9605\u8bfb~\u5982\u6709\u4e0d\u8db3\uff0c\u6b22\u8fce\u5efa\u8bae\u4e0e\u6307\u6b63~~~\uff1a\uff09<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4e00\u3001 1\u3001\u5148\u770b\u4e00\u4e2a\u793a\u4f8b1\uff1a var a = &#8216;abc&#8217;; alert(window.a) \/\/abc aler &hellip; <a href=\"http:\/\/www.imzouyang.com\/blog\/archives\/599.html\" class=\"read-more\">\u7ee7\u7eed\u9605\u8bfb <span class=\"screen-reader-text sr-only\">js\u6280\u5de7\uff1a\u907f\u514d\u83b7\u53d6\u53d8\u91cf\u6216\u5c5e\u6027\u62a5\u9519<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"aside","meta":[],"categories":[30],"tags":[],"_links":{"self":[{"href":"http:\/\/www.imzouyang.com\/blog\/wp-json\/wp\/v2\/posts\/599"}],"collection":[{"href":"http:\/\/www.imzouyang.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.imzouyang.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.imzouyang.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.imzouyang.com\/blog\/wp-json\/wp\/v2\/comments?post=599"}],"version-history":[{"count":2,"href":"http:\/\/www.imzouyang.com\/blog\/wp-json\/wp\/v2\/posts\/599\/revisions"}],"predecessor-version":[{"id":2057,"href":"http:\/\/www.imzouyang.com\/blog\/wp-json\/wp\/v2\/posts\/599\/revisions\/2057"}],"wp:attachment":[{"href":"http:\/\/www.imzouyang.com\/blog\/wp-json\/wp\/v2\/media?parent=599"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.imzouyang.com\/blog\/wp-json\/wp\/v2\/categories?post=599"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.imzouyang.com\/blog\/wp-json\/wp\/v2\/tags?post=599"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}