{"id":183788,"date":"2024-11-10T07:44:18","date_gmt":"2024-11-09T23:44:18","guid":{"rendered":"https:\/\/server.hk\/cnblog\/183788\/"},"modified":"2024-11-10T07:44:18","modified_gmt":"2024-11-09T23:44:18","slug":"%e4%bd%bf%e7%94%a8linq%e4%bf%ae%e6%94%b9%e6%95%b8%e6%93%9a%e5%ba%ab%e4%b8%ad%e7%9a%84%e4%b8%80%e5%88%97%e6%95%b8%e6%93%9a-linq-%e4%bf%ae%e6%94%b9%e4%b8%80%e5%88%97%e6%95%b8%e6%93%9a%e5%ba%ab","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/183788\/","title":{"rendered":"\u4f7f\u7528LINQ\u4fee\u6539\u6578\u64da\u5eab\u4e2d\u7684\u4e00\u5217\u6578\u64da (linq \u4fee\u6539\u4e00\u5217\u6578\u64da\u5eab)"},"content":{"rendered":"<h1 id=\"%e4%bd%bf%e7%94%a8linq%e4%bf%ae%e6%94%b9%e6%95%b8%e6%93%9a%e5%ba%ab%e4%b8%ad%e7%9a%84%e4%b8%80%e5%88%97%e6%95%b8%e6%93%9a-SXTTuzaqhl\">\u4f7f\u7528LINQ\u4fee\u6539\u6578\u64da\u5eab\u4e2d\u7684\u4e00\u5217\u6578\u64da<\/h1>\n<p>\u5728\u73fe\u4ee3\u61c9\u7528\u7a0b\u5e8f\u958b\u767c\u4e2d\uff0c\u6578\u64da\u5eab\u64cd\u4f5c\u662f\u4e0d\u53ef\u6216\u7f3a\u7684\u4e00\u90e8\u5206\u3002LINQ\uff08Language Integrated Query\uff09\u662f\u4e00\u7a2e\u5f37\u5927\u7684\u67e5\u8a62\u8a9e\u8a00\uff0c\u80fd\u5920\u8b93\u958b\u767c\u8005\u4ee5\u66f4\u76f4\u89c0\u7684\u65b9\u5f0f\u64cd\u4f5c\u6578\u64da\u5eab\u3002\u672c\u6587\u5c07\u63a2\u8a0e\u5982\u4f55\u4f7f\u7528LINQ\u4f86\u4fee\u6539\u6578\u64da\u5eab\u4e2d\u7684\u4e00\u5217\u6578\u64da\uff0c\u4e26\u63d0\u4f9b\u76f8\u95dc\u7684\u793a\u4f8b\u548c\u4ee3\u78bc\u7247\u6bb5\u3002<\/p>\n<h2 id=\"linq%e7%9a%84%e5%9f%ba%e6%9c%ac%e6%a6%82%e5%bf%b5-SXTTuzaqhl\">LINQ\u7684\u57fa\u672c\u6982\u5ff5<\/h2>\n<p>LINQ\u662f\u4e00\u7a2e\u96c6\u6210\u65bc.NET\u8a9e\u8a00\u4e2d\u7684\u67e5\u8a62\u8a9e\u8a00\uff0c\u5141\u8a31\u958b\u767c\u8005\u4f7f\u7528\u985e\u4f3c\u65bcSQL\u7684\u8a9e\u6cd5\u4f86\u67e5\u8a62\u548c\u64cd\u4f5c\u6578\u64da\u3002LINQ\u652f\u6301\u591a\u7a2e\u6578\u64da\u6e90\uff0c\u5305\u62ec\u6578\u64da\u5eab\u3001XML\u6587\u4ef6\u548c\u96c6\u5408\u7b49\u3002\u4f7f\u7528LINQ\u9032\u884c\u6578\u64da\u5eab\u64cd\u4f5c\u6642\uff0c\u901a\u5e38\u6703\u4f7f\u7528Entity Framework\uff08EF\uff09\u4f5c\u70baORM\uff08\u5c0d\u8c61\u95dc\u4fc2\u6620\u5c04\uff09\u5de5\u5177\uff0c\u9019\u6a23\u53ef\u4ee5\u66f4\u65b9\u4fbf\u5730\u5c07\u6578\u64da\u5eab\u4e2d\u7684\u6578\u64da\u6620\u5c04\u5230\u5c0d\u8c61\u6a21\u578b\u4e2d\u3002<\/p>\n<h2 id=\"%e4%bf%ae%e6%94%b9%e6%95%b8%e6%93%9a%e5%ba%ab%e4%b8%ad%e7%9a%84%e4%b8%80%e5%88%97%e6%95%b8%e6%93%9a-SXTTuzaqhl\">\u4fee\u6539\u6578\u64da\u5eab\u4e2d\u7684\u4e00\u5217\u6578\u64da<\/h2>\n<p>\u5728\u4f7f\u7528LINQ\u4fee\u6539\u6578\u64da\u5eab\u4e2d\u7684\u4e00\u5217\u6578\u64da\u6642\uff0c\u9996\u5148\u9700\u8981\u78ba\u4fdd\u5df2\u7d93\u8a2d\u7f6e\u597dEntity Framework\u4e26\u4e14\u5df2\u7d93\u9023\u63a5\u5230\u6578\u64da\u5eab\u3002\u4ee5\u4e0b\u662f\u4fee\u6539\u6578\u64da\u5eab\u4e2d\u67d0\u4e00\u5217\u6578\u64da\u7684\u57fa\u672c\u6b65\u9a5f\uff1a<\/p>\n<h3 id=\"%e6%ad%a5%e9%a9%9f1%ef%bc%9a%e8%a8%ad%e7%bd%ae%e6%95%b8%e6%93%9a%e4%b8%8a%e4%b8%8b%e6%96%87-SXTTuzaqhl\">\u6b65\u9a5f1\uff1a\u8a2d\u7f6e\u6578\u64da\u4e0a\u4e0b\u6587<\/h3>\n<pre><code>using (var context = new YourDbContext())\n{\n    \/\/ \u9032\u884c\u6578\u64da\u64cd\u4f5c\n}<\/code><\/pre>\n<p>\u5728\u9019\u6bb5\u4ee3\u78bc\u4e2d\uff0c<code>YourDbContext<\/code>\u662f\u60a8\u5b9a\u7fa9\u7684\u6578\u64da\u4e0a\u4e0b\u6587\u985e\uff0c\u9019\u500b\u985e\u901a\u5e38\u6703\u7e7c\u627f\u81ea<code>DbContext<\/code>\u3002<\/p>\n<h3 id=\"%e6%ad%a5%e9%a9%9f2%ef%bc%9a%e6%9f%a5%e8%a9%a2%e8%a6%81%e4%bf%ae%e6%94%b9%e7%9a%84%e6%95%b8%e6%93%9a-SXTTuzaqhl\">\u6b65\u9a5f2\uff1a\u67e5\u8a62\u8981\u4fee\u6539\u7684\u6578\u64da<\/h3>\n<p>\u4f7f\u7528LINQ\u67e5\u8a62\u8981\u4fee\u6539\u7684\u6578\u64da\u3002\u4f8b\u5982\uff0c\u5047\u8a2d\u6211\u5011\u6709\u4e00\u500b\u540d\u70ba<code>Users<\/code>\u7684\u8868\uff0c\u6211\u5011\u60f3\u8981\u4fee\u6539\u67d0\u500b\u7528\u6236\u7684\u96fb\u5b50\u90f5\u4ef6\u5730\u5740\uff1a<\/p>\n<pre><code>var user = context.Users.FirstOrDefault(u =&gt; u.Id == userId);<\/code><\/pre>\n<p>\u5728\u9019\u88e1\uff0c<code>userId<\/code>\u662f\u6211\u5011\u8981\u67e5\u8a62\u7684\u7528\u6236\u7684ID\u3002<\/p>\n<h3 id=\"%e6%ad%a5%e9%a9%9f3%ef%bc%9a%e4%bf%ae%e6%94%b9%e6%95%b8%e6%93%9a-SXTTuzaqhl\">\u6b65\u9a5f3\uff1a\u4fee\u6539\u6578\u64da<\/h3>\n<p>\u4e00\u65e6\u627e\u5230\u8981\u4fee\u6539\u7684\u6578\u64da\uff0c\u6211\u5011\u53ef\u4ee5\u76f4\u63a5\u4fee\u6539\u5176\u5c6c\u6027\uff1a<\/p>\n<pre><code>if (user != null)\n{\n    user.Email = \"newemail@example.com\";\n}<\/code><\/pre>\n<h3 id=\"%e6%ad%a5%e9%a9%9f4%ef%bc%9a%e4%bf%9d%e5%ad%98%e6%9b%b4%e6%94%b9-SXTTuzaqhl\">\u6b65\u9a5f4\uff1a\u4fdd\u5b58\u66f4\u6539<\/h3>\n<p>\u6700\u5f8c\uff0c\u6211\u5011\u9700\u8981\u5c07\u66f4\u6539\u4fdd\u5b58\u5230\u6578\u64da\u5eab\u4e2d\uff1a<\/p>\n<pre><code>context.SaveChanges();<\/code><\/pre>\n<p>\u9019\u6a23\uff0c\u4fee\u6539\u5c31\u6703\u88ab\u63d0\u4ea4\u5230\u6578\u64da\u5eab\uff0c\u5b8c\u6210\u6574\u500b\u904e\u7a0b\u3002<\/p>\n<h2 id=\"%e5%ae%8c%e6%95%b4%e7%a4%ba%e4%be%8b-SXTTuzaqhl\">\u5b8c\u6574\u793a\u4f8b<\/h2>\n<p>\u4ee5\u4e0b\u662f\u4e00\u500b\u5b8c\u6574\u7684\u793a\u4f8b\uff0c\u5c55\u793a\u5982\u4f55\u4f7f\u7528LINQ\u4fee\u6539\u6578\u64da\u5eab\u4e2d\u7684\u4e00\u5217\u6578\u64da\uff1a<\/p>\n<pre><code>using (var context = new YourDbContext())\n{\n    var userId = 1; \/\/ \u5047\u8a2d\u6211\u5011\u8981\u4fee\u6539ID\u70ba1\u7684\u7528\u6236\n    var user = context.Users.FirstOrDefault(u =&gt; u.Id == userId);\n    \n    if (user != null)\n    {\n        user.Email = \"newemail@example.com\"; \/\/ \u4fee\u6539\u96fb\u5b50\u90f5\u4ef6\u5730\u5740\n        context.SaveChanges(); \/\/ \u4fdd\u5b58\u66f4\u6539\n    }\n}<\/code><\/pre>\n<h2 id=\"%e6%b3%a8%e6%84%8f%e4%ba%8b%e9%a0%85-SXTTuzaqhl\">\u6ce8\u610f\u4e8b\u9805<\/h2>\n<ul>\n<li>\u5728\u9032\u884c\u6578\u64da\u4fee\u6539\u6642\uff0c\u52d9\u5fc5\u78ba\u4fdd\u67e5\u8a62\u5230\u7684\u5c0d\u8c61\u4e0d\u70ba<code>null<\/code>\uff0c\u4ee5\u907f\u514d\u5f15\u767c\u7570\u5e38\u3002<\/li>\n<li>\u5728\u9032\u884c\u6279\u91cf\u66f4\u65b0\u6642\uff0c\u8003\u616e\u4f7f\u7528<code>DbSet.UpdateRange()<\/code>\u65b9\u6cd5\u4f86\u63d0\u9ad8\u6027\u80fd\u3002<\/li>\n<li>\u5728\u751f\u7522\u74b0\u5883\u4e2d\uff0c\u5efa\u8b70\u4f7f\u7528\u4e8b\u52d9\u4f86\u78ba\u4fdd\u6578\u64da\u7684\u4e00\u81f4\u6027\u3002<\/li>\n<\/ul>\n<h2 id=\"%e7%b8%bd%e7%b5%90-SXTTuzaqhl\">\u7e3d\u7d50<\/h2>\n<p>\u4f7f\u7528LINQ\u4f86\u4fee\u6539\u6578\u64da\u5eab\u4e2d\u7684\u4e00\u5217\u6578\u64da\u662f\u4e00\u500b\u7c21\u55ae\u800c\u6709\u6548\u7684\u904e\u7a0b\u3002\u901a\u904e\u8a2d\u7f6e\u6578\u64da\u4e0a\u4e0b\u6587\u3001\u67e5\u8a62\u76ee\u6a19\u6578\u64da\u3001\u4fee\u6539\u5c6c\u6027\u4ee5\u53ca\u4fdd\u5b58\u66f4\u6539\uff0c\u958b\u767c\u8005\u53ef\u4ee5\u8f15\u9b06\u5730\u9032\u884c\u6578\u64da\u64cd\u4f5c\u3002\u9019\u7a2e\u65b9\u6cd5\u4e0d\u50c5\u63d0\u9ad8\u4e86\u958b\u767c\u6548\u7387\uff0c\u9084\u4f7f\u4ee3\u78bc\u66f4\u52a0\u53ef\u8b80\u548c\u6613\u65bc\u7dad\u8b77\u3002<\/p>\n<p>\u5982\u679c\u60a8\u6b63\u5728\u5c0b\u627e\u9ad8\u6548\u7684\u6578\u64da\u5b58\u5132\u89e3\u6c7a\u65b9\u6848\uff0c\u8003\u616e\u4f7f\u7528<a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a>\u4f86\u6258\u7ba1\u60a8\u7684\u61c9\u7528\u7a0b\u5e8f\uff0c\u9019\u6a23\u53ef\u4ee5\u78ba\u4fdd\u60a8\u7684\u6578\u64da\u5b89\u5168\u4e14\u96a8\u6642\u53ef\u7528\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5b78\u7fd2\u5982\u4f55\u4f7f\u7528LINQ\u8f15\u9b06\u4fee\u6539\u6578\u64da\u5eab\u4e2d\u7684\u4e00\u5217\u6578\u64da\uff0c\u63d0\u5347\u6578\u64da\u64cd\u4f5c\u6548\u7387\uff0c\u7c21\u5316\u958b\u767c\u6d41\u7a0b\u3002<\/p>\n","protected":false},"author":0,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[101],"tags":[],"class_list":["post-183788","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/183788","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/types\/post"}],"replies":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/comments?post=183788"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/183788\/revisions"}],"predecessor-version":[{"id":183789,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/183788\/revisions\/183789"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=183788"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=183788"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=183788"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}