{"id":5360,"date":"2012-08-07T09:52:55","date_gmt":"2012-08-07T00:52:55","guid":{"rendered":"http:\/\/www.gesource.jp\/weblog\/?p=5360"},"modified":"2017-07-16T11:10:27","modified_gmt":"2017-07-16T02:10:27","slug":"delphi%e3%81%a7raii","status":"publish","type":"post","link":"https:\/\/www.gesource.jp\/weblog\/?p=5360","title":{"rendered":"Delphi\u3067RAII"},"content":{"rendered":"<p>Delphi\u306e\u30a4\u30f3\u30bf\u30fc\u30d5\u30a7\u30fc\u30b9\u3092\u4f7f\u3046\u3068\u3001\u53c2\u7167\u30ab\u30a6\u30f3\u30c8\u304c0\u306b\u306a\u3063\u305f\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306f\u81ea\u52d5\u3067\u7834\u68c4\u3055\u308c\u307e\u3059\u3002<br \/>\n\u3053\u306e\u6a5f\u80fd\u3092\u4f7f\u3063\u3066\u3001\u5909\u6570\u304c\u30b9\u30b3\u30fc\u30d7\u3092\u96e2\u308c\u305f\u6642\u306b\u30ea\u30bd\u30fc\u30b9\u3092\u8fd4\u5374\u3059\u308bRAII\u3092\u5b9f\u73fe\u3067\u304d\u307e\u3059\u3002<\/p>\n<p>\u6b21\u306e\u30b5\u30f3\u30d7\u30eb\u30d7\u30ed\u30b0\u30e9\u30e0\u306f\u3001\u30dc\u30bf\u30f3\u3092\u62bc\u3057\u305f\u6642\u306b\u6642\u9593\u306e\u304b\u304b\u308b\u51e6\u7406\u3092\u884c\u3044\u307e\u3059\u3002<br \/>\n\u51e6\u7406\u4e2d\u306f\u30ab\u30fc\u30bd\u30eb\u3092\u7802\u6642\u8a08\u306b\u3057\u3066\u3001\u51e6\u7406\u304c\u7d42\u308f\u3063\u305f\u3089\u30ab\u30fc\u30bd\u30eb\u3092\u5143\u306b\u623b\u3057\u307e\u3059\u3002<\/p>\n<pre><code>procedure TForm1.Button1Click(Sender: TObject);\nvar\n  Save_Cursor: TCursor;\nbegin\n  Save_Cursor := Screen.Cursor; \/\/\u73fe\u5728\u306e\u30ab\u30fc\u30eb\u7956\u3092\u4fdd\u5b58\n  Screen.Cursor := crHourGlass; \/\/\u30ab\u30fc\u30bd\u30eb\u3092\u7802\u6642\u8a08\u306b\u5909\u66f4\n  try\n    Sleep(5000);  \/\/\u6642\u9593\u306e\u304b\u304b\u308b\u51e6\u7406\n  finally\n    Screen.Cursor := Save_Cursor; \/\/\u30ab\u30fc\u30bd\u30eb\u3092\u5143\u306b\u623b\u3059\n  end;\nend;\n<\/code><\/pre>\n<p>RAII\u3092\u4f7f\u3046\u3068\u3001\u6b21\u306e\u3088\u3046\u306a\u30b3\u30fc\u30c9\u3092\u66f8\u304f\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<br \/>\n\u30b3\u30fc\u30c9\u304c\u305a\u3044\u3076\u3093\u3068\u898b\u3084\u3059\u304f\u306a\u308a\u307e\u3059\u3002<\/p>\n<pre><code>procedure TForm1.Button2Click(Sender: TObject);\nvar\n  Cursor: IRAIICursor;\nbegin\n  Cursor := CreateRAIICursor(crHourGlass); \/\/\u30ab\u30fc\u30bd\u30eb\u3092\u7802\u6642\u8a08\u306b\u5909\u66f4\n  Sleep(5000);  \/\/\u6642\u9593\u306e\u304b\u304b\u308b\u51e6\u7406\nend;  \/\/\u30b9\u30b3\u30fc\u30d7\u3092\u96e2\u308c\u308b\u3068\u30ab\u30fc\u30bd\u30eb\u3092\u5143\u306b\u623b\u3059\n<\/code><\/pre>\n<p>\u5b9f\u88c5\u65b9\u6cd5\u306f\u6b21\u306e\u3088\u3046\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n<pre><code>type\n  \/\/\/ &lt;summary&gt;\u30ab\u30fc\u30bd\u30eb\u3092\u7ba1\u7406\u3059\u308bRAII\u306e\u30a4\u30f3\u30bf\u30fc\u30d5\u30a7\u30fc\u30b9&lt;\/summary&gt;\n  IRAIICursor = interface\n  end;\n\n  \/\/\/ &lt;summary&gt;RAII\u306e\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3092\u53d6\u5f97\u3059\u308b&lt;\/summary&gt;\n  \/\/\/ &lt;param name=\"Cursor\"&gt;\u5909\u66f4\u3059\u308b\u30ab\u30fc\u30bd\u30eb&lt;\/param&gt;\n  \/\/\/ &lt;returns&gt;RAII\u306e\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3002\u5b9f\u4f53\u306fTRAIICursor\u30af\u30e9\u30b9&lt;\/returns&gt;\n  function CreateRAIICursor(Cursor: TCursor):IRAIICursor;\n\nimplementation\n\ntype\n  \/\/\/ &lt;summary&gt;IRAIICursor\u306e\u5b9f\u88c5\u3002\u3053\u306e\u30af\u30e9\u30b9\u306f\u516c\u958b\u3057\u306a\u3044\u3002&lt;\/summary&gt;\n  TRAIICursor = class(TInterfacedObject, IRAIICursor)\n  private\n    FCursor: TCursor; \/\/\u5909\u66f4\u524d\u306e\u30ab\u30fc\u30bd\u30eb\n  public\n    constructor Create(Cursor: TCursor);\n    destructor Destroy; override;\n  end;\n\nconstructor TRAIICursor.Create(Cursor: TCursor);\nbegin\n  FCursor := Screen.Cursor;\n  Screen.Cursor := Cursor;\nend;\n\ndestructor TRAIICursor.Destroy;\nbegin\n  Screen.Cursor := FCursor; \/\/\u30ab\u30fc\u30bd\u30eb\u3092\u5143\u306b\u623b\u3059\nend;\n\nfunction CreateRAIICursor(Cursor: TCursor):IRAIICursor;\nbegin\n  Result := TRAIICursor.Create(Cursor);\nend;\n<\/code><\/pre>\n<p>\u306a\u304b\u306a\u304b\u4fbf\u5229\u3067\u306f\u306a\u3044\u304b\u3068\u601d\u3044\u307e\u3059\u304c\u3001\u3044\u304b\u304c\u3067\u3057\u3087\u3046\u304b\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Delphi\u306e\u30a4\u30f3\u30bf\u30fc\u30d5\u30a7\u30fc\u30b9\u3092\u4f7f\u3046\u3068\u3001\u53c2\u7167\u30ab\u30a6\u30f3\u30c8\u304c0\u306b\u306a\u3063\u305f\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306f\u81ea\u52d5\u3067\u7834\u68c4\u3055\u308c\u307e\u3059\u3002 \u3053\u306e\u6a5f\u80fd\u3092\u4f7f\u3063\u3066\u3001\u5909\u6570\u304c\u30b9\u30b3\u30fc\u30d7\u3092\u96e2\u308c\u305f\u6642\u306b\u30ea\u30bd\u30fc\u30b9\u3092\u8fd4\u5374\u3059\u308bRAII\u3092\u5b9f\u73fe\u3067\u304d\u307e\u3059\u3002 \u6b21\u306e\u30b5\u30f3\u30d7\u30eb\u30d7\u30ed\u30b0\u30e9\u30e0\u306f\u3001\u30dc\u30bf\u30f3 &#8230;<\/p>\n<p><a href=\"https:\/\/www.gesource.jp\/weblog\/?p=5360\" class=\"more-link\">Continue reading &lsquo;Delphi\u3067RAII&rsquo; &raquo;<\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[48],"tags":[156,42,44],"class_list":["post-5360","post","type-post","status-publish","format-standard","hentry","category-delphi","tag-delphi","tag-tips","tag-vcl"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.gesource.jp\/weblog\/index.php?rest_route=\/wp\/v2\/posts\/5360","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.gesource.jp\/weblog\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.gesource.jp\/weblog\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.gesource.jp\/weblog\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.gesource.jp\/weblog\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=5360"}],"version-history":[{"count":0,"href":"https:\/\/www.gesource.jp\/weblog\/index.php?rest_route=\/wp\/v2\/posts\/5360\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.gesource.jp\/weblog\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=5360"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.gesource.jp\/weblog\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=5360"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.gesource.jp\/weblog\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=5360"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}