{"id":17716,"date":"2023-02-20T16:49:00","date_gmt":"2023-02-20T08:49:00","guid":{"rendered":"https:\/\/docs.pingcode.com\/?p=17716"},"modified":"2023-02-20T16:49:05","modified_gmt":"2023-02-20T08:49:05","slug":"%e5%af%b9%e4%ba%8eqfile%ef%bc%8cdelete%ef%bc%8cdeletelater%ef%bc%8cclose%e6%9c%89%e4%bb%80%e4%b9%88%e5%8c%ba%e5%88%ab","status":"publish","type":"post","link":"https:\/\/docs.pingcode.com\/ask\/17716.html","title":{"rendered":"\u5bf9\u4e8eQFile\uff0cdelete\uff0cdeletelater()\uff0cclose()\u6709\u4ec0\u4e48\u533a\u522b"},"content":{"rendered":"\n
\n

\u5bf9\u4e8eQFile\uff0cdelete\uff0cdeletelater()\uff0cclose()\u7684\u533a\u522b\u662f\uff1adelete \u662fC++\u7684\u5185\u5b58\u91ca\u653e\uff0c\u4f1a\u8c03\u7528QFile\u7684\u6790\u6784\u51fd\u6570\uff1bdeletelater\u662fQt Object\u5143\u5bf9\u8c61\u7cfb\u7edf\u63d0\u4f9b\u7684\u5bf9\u8c61\u5220\u9664\u51fd\u6570\uff0c\u4e5f\u4f1a\u8c03\u7528delete\u91ca\u653e\u5bf9\u8c61\uff1bclose\u662f\u6587\u4ef6\u5173\u95ed\uff0c\u5bf9\u5e94open\u3002<\/p>\n<\/blockquote>\n\n\n

\n
\"\"<\/figure><\/div>\n\n\n

\u4e00\u3001QFile\uff0cdelete\uff0cdeletelater()\uff0cclose()\u7684\u533a\u522b<\/strong><\/h2>\n\n\n\n

delete \u662fC++\u7684\u5185\u5b58\u91ca\u653e\uff0c\u4f1a\u8c03\u7528QFile\u7684\u6790\u6784\u51fd\u6570\uff0c\u4f46\u662f\u6790\u6784\u51fd\u6570\u4e2d\u6709\u6ca1\u6709\u9ed8\u8ba4close\u6253\u5f00\u7684\u6587\u4ef6\u3002<\/p>\n\n\n\n

deletelater\u662fQt Object\u5143\u5bf9\u8c61\u7cfb\u7edf\u63d0\u4f9b\u7684\u5bf9\u8c61\u5220\u9664\u51fd\u6570\uff0c\u4e5f\u4f1a\u8c03\u7528delete\u91ca\u653e\u5bf9\u8c61\uff0c\u4f46\u662f\u4f1a\u5728\u4e00\u4e2a\u4e8b\u4ef6\u5faa\u73af\u7ed3\u675f\u540e\u91ca\u653e\uff08Qt Event Loop\uff09\uff0c\u53ef\u4ee5\u7406\u89e3\u4e3a\u628a\u8fd9\u4e2a\u5bf9\u8c61\u52a0\u5165\u4e86\u4e00\u4e2a\u5f85\u91ca\u653e\u961f\u5217\uff0cQt\u4e8b\u4ef6\u5faa\u73af\u5b8c\u6210\u540e\u4f1a\u53bb\u91ca\u653e\u8fd9\u4e2a\u5bf9\u8c61\u7684\u5185\u5b58\uff0c\u5efa\u8bae\u4e0d\u7406\u89e3\u673a\u5236\u522b\u4e71\u7528\uff0c\u7a0b\u5e8f\u590d\u6742\u4e86\u5d29\u6e83\u90fd\u4e0d\u77e5\u9053\u600e\u4e48\u53bb\u67e5\u3002<\/p>\n\n\n\n

\u8fd4\u56de\u5230\u4e8b\u4ef6\u5faa\u73af\u540e\uff0c\u8c03\u7528deleteLater()\u7684\u5bf9\u8c61\u624d\u4f1a\u88ab\u9500\u6bc1\uff0c\u5426\u5219\u4e0d\u6267\u884c\u3002<\/p>\n\n\n\n

\u5982\u679c\u7ebf\u7a0b\u4e2d\u6ca1\u6709\u8fd0\u884c\u7740\u7684\u4e8b\u4ef6\u5faa\u73af\uff0c\u7ebf\u7a0b\u4e2d\u7684\u5bf9\u8c61\u8c03\u7528\u4e86deleteLater()\uff0c\u5f53\u7ebf\u7a0b\u7ed3\u675f\u540e\u5bf9\u8c61\u624d\u88ab\u9500\u6bc1\u3002\u5f53\u540d\u5217\u524d\u8305\u6b21QDeferredDeleteEvent\u4f20\u9012\u7ed9\u4e8b\u4ef6\u5faa\u73af\u540e\uff0c\u5bf9\u8c61\u7684\u4efb\u4f55\u5f85\u5904\u7406\u4e8b\u4ef6(pending events)\u90fd\u4ece\u4e8b\u4ef6\u961f\u5217\u4e2d\u79fb\u9664\u3002<\/p>\n\n\n\n

Qt\u4e2d\u4e0d\u5efa\u8bae\u624b\u52a8delete\u6389QObject\u5bf9\u8c61\u3002\u539f\u56e0\u4e00\uff1a\u4e0d\u6ce8\u610f\u7236\u5b50\u5173\u7cfb\u4f1a\u5bfc\u81f4\u67d0\u4e2a\u5bf9\u8c61\u6790\u6784\u4e24\u6b21\uff0c\u4e00\u6b21\u662f\u624b\u52a8\u6790\u6784\uff0c\u8fd8\u6709\u4e00\u6b21\u662fparent\u6790\u6784\uff0c\u540e\u8005\u53ef\u80fd\u4f1a\u51fa\u73b0delete\u5806\u4e0a\u7684\u5bf9\u8c61\u3002<\/p>\n\n\n\n

\u5ef6\u4f38\u9605\u8bfb\uff1a<\/strong><\/p>\n\n\n\n

\u4e8c\u3001QFile\u6587\u4ef6\u5982\u679c\u4e0d\u5b58\u5728\u5219\u521b\u5efa\u7684\u65b9\u6cd5<\/strong><\/h2>\n\n\n\n

    QFile f(“.\/1234.ini”);<\/p>\n\n\n\n

    if(!f.open(QIODevice::Append))<\/p>\n\n\n\n

    {<\/p>\n\n\n\n

        return 0;<\/p>\n\n\n\n

    }<\/p>\n\n\n\n

open\u91cc\u7684\u6253\u5f00\u6a21\u5f0f\u4e3aQIODevice::WriteOnly\u3001QIODevice::ReadWrite\u3001QIODevice::Append\u8fd9\u4e09\u79cd\u7684\u8bdd\uff0c\u6587\u4ef6\u4e0d\u5b58\u5728\u5219\u4f1a\u81ea\u52a8\u521b\u5efa\u51fa\u4e00\u4e2a\u7a7a\u6587\u4ef6\u51fa\u6765\u3002\u5176\u4ed6\u6253\u5f00\u6a21\u5f0f\u5c31\u4e0d\u884c\u3002\u5df2\u6d4b\u8bd5\u3002<\/p>\n\n\n\n

open\u6253\u5f00\u7684\u51e0\u79cd\u6a21\u5f0f\u5982\u4e0b:<\/p>\n\n\n\n

QIODevice::ReadOnly  \u4ee5\u53ea\u8bfb\u65b9\u5f0f\u6253\u5f00\u6587\u4ef6<\/p>\n\n\n\n

QIODevice::WriteOnly \u53ea\u5199\u65b9\u5f0f<\/p>\n\n\n\n

QIODevice::ReadWrite \u8bfb\u5199\u65b9\u5f0f<\/p>\n\n\n\n

QIODevice::Append \u8ffd\u52a0\u6a21\u5f0f\u6253\u5f00\uff0c\u65b0\u5199\u5165\u6587\u4ef6\u7684\u6570\u636e\u6dfb\u52a0\u5230\u6587\u4ef6\u5c3e\u90e8<\/p>\n\n\n\n

QIODevice::Truncate  \u622a\u53d6\u65b9\u5f0f\u6253\u5f00\u6587\u4ef6\uff0c\u6587\u4ef6\u539f\u6709\u7684\u5185\u5bb9\u5168\u90e8\u88ab\u5220\u9664<\/p>\n\n\n\n

QIODevice::Text\u6587\u672c\u65b9\u5f0f\u6253\u5f00\u6587\u4ef6\uff0c\u8bfb\u53d6\u65f6\u201c\\n\u201d\u88ab\u81ea\u52a8\u7ffb\u8bd1\u4e3a\u6362\u884c\u7b26<\/p>\n\n\n\n

\u8fd9\u4e9b\u53d6\u503c\u53ef\u4ee5\u7528\u201c|\u201d\u7ec4\u5408\u4f7f\u7528\uff0c\u4f8b\u5982 QIODevice::ReadOnly | QIODevice::Text \u8868\u793a\u4ee5\u53ea\u8bfb\u548c\u6587\u672c\u65b9\u5f0f\u6253\u5f00\u6587\u4ef6\u3002<\/p>\n\n\n\n

\u4ee5\u4e0a\u5c31\u662f\u5173\u4e8e\u5bf9\u4e8eQFile\uff0cdelete\uff0cdeletelater()\uff0cclose()\u6709\u4ec0\u4e48\u533a\u522b\u7684\u5185\u5bb9\u5e0c\u671b\u5bf9\u5927\u5bb6\u6709\u5e2e\u52a9\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"\u5bf9\u4e8eQFile\uff0cdelete\uff0cdeletelater()\uff0cclose()\u7684\u533a\u522b\u662f\uff1adelete \u662fC++\u7684\u5185\u5b58 […]","protected":false},"author":1,"featured_media":17717,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[37],"tags":[],"acf":[],"_links":{"self":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts\/17716"}],"collection":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/comments?post=17716"}],"version-history":[{"count":0,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts\/17716\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/media\/17717"}],"wp:attachment":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/media?parent=17716"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/categories?post=17716"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/tags?post=17716"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}