{"id":208108,"date":"2025-07-08T17:49:42","date_gmt":"2025-07-08T09:49:42","guid":{"rendered":"https:\/\/server.hk\/cnblog\/208108\/"},"modified":"2025-07-08T17:49:42","modified_gmt":"2025-07-08T09:49:42","slug":"golang-%e4%b8%ad%e4%bd%bf%e7%94%a8-ioutil-readall-%e5%87%ba%e7%8e%b0%e6%97%a0%e6%95%88%e5%86%85%e5%ad%98%e5%9c%b0%e5%9d%80","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/208108\/","title":{"rendered":"Golang \u4e2d\u4f7f\u7528 ioutil.ReadAll() \u51fa\u73b0\u201c\u65e0\u6548\u5185\u5b58\u5730\u5740\u201d"},"content":{"rendered":"<p><b><\/b> <\/p>\n<p>\u5f53\u524d\u4f4d\u7f6e\uff1a <span>&gt;<\/span> <span>&gt;<\/span> <span>&gt;<\/span> <span>&gt;<\/span> <span>Golang \u4e2d\u4f7f\u7528 ioutil.ReadAll() \u51fa\u73b0\u201c\u65e0\u6548\u5185\u5b58\u5730\u5740\u201d<\/span><\/p>\n<p><span>\u6765\u6e90\uff1astackoverflow<\/span><br \/>\n<span>2024-04-29 08:09:32<\/span><br \/>\n<span><i><\/i>0\u6d4f\u89c8<\/span><br \/>\n<span style=\"cursor: pointer\"><i><\/i>\u6536\u85cf<\/span> <\/p>\n<p>\u5927\u5bb6\u597d\uff0c\u4eca\u5929\u672c\u4eba\u7ed9\u5927\u5bb6\u5e26\u6765\u6587\u7ae0<span style=\"color: #FF6600;, Helvetica, Arial, sans-serif;font-size: 14px;background-color: #FFFFFF\">\u300aGolang \u4e2d\u4f7f\u7528 ioutil.ReadAll() \u51fa\u73b0\u201c\u65e0\u6548\u5185\u5b58\u5730\u5740\u201d\u300b<\/span>\uff0c\u6587\u4e2d\u5185\u5bb9\u4e3b\u8981\u6d89\u53ca\u5230<span style=\"color: #FF6600;, Helvetica, Arial, sans-serif;font-size: 14px;background-color: #FFFFFF\"><span style=\"color: #FF6600;, Helvetica, Arial, sans-serif;font-size: 14px;background-color: #FFFFFF\"><\/span><\/span>\uff0c\u5982\u679c\u4f60\u5bf9<span style=\"color: #FF6600;, Helvetica, Arial, sans-serif;font-size: 14px;background-color: #FFFFFF\">Golang<\/span>\u65b9\u9762\u7684\u77e5\u8bc6\u70b9\u611f\u5174\u8da3\uff0c\u90a3\u5c31\u8bf7\u5404\u4f4d\u670b\u53cb\u7ee7\u7eed\u770b\u4e0b\u53bb\u5427~\u5e0c\u671b\u80fd\u771f\u6b63\u5e2e\u5230\u4f60\u4eec\uff0c\u8c22\u8c22\uff01<\/p>\n<p> \u95ee\u9898\u5185\u5bb9<br \/>\n <\/p>\n<p>\u6211\u76ee\u524d\u6b63\u5728\u5b66\u4e60 golang\uff08\u5230\u76ee\u524d\u4e3a\u6b62\u6211\u5f88\u559c\u6b22\u5b83\uff09\u3002\u4f46\u4e0d\u5e78\u7684\u662f\uff0c\u6211\u5df2\u7ecf\u88ab\u56f0\u4e86\u51e0\u4e2a\u5c0f\u65f6\uff0c\u800c\u4e14\u6211\u5728 google \u4e0a\u4f3c\u4e4e\u627e\u4e0d\u5230\u4efb\u4f55\u89e3\u51b3\u65b9\u6848\u3002<\/p>\n<p>\u8fd9\u5c31\u662f\u6211\u7684\u95ee\u9898\u3002\u6211\u6709\u8fd9\u6bb5\u4ee3\u7801\uff08\u6765\u81ea\u6559\u7a0b\uff09\uff1a<\/p>\n<pre>func main() {\n    var s sitemapindex\n\n    resp, _ := http.get(\"https:\/\/www.washingtonpost.com\/news-sitemaps\/index.xml\")\n    bytes, _ := ioutil.readall(resp.body)\n    resp.body.close()\n\n    xml.unmarshal(bytes, &amp;s)\n\n    for _, location := range s.locations {\n        resp, _ := http.get(location)\n        ioutil.readall(resp.body)\n\n    }\n\n}<\/pre>\n<p>\u6211\u77e5\u9053\uff0c\u6211\u7684\u4ee3\u7801\u4e0d\u5b8c\u6574\uff0c\u4f46\u90a3\u662f\u56e0\u4e3a\u6211\u5220\u9664\u4e86\u4e0d\u4f1a\u5bfc\u81f4\u95ee\u9898\u7684\u90e8\u5206\uff0c\u4ee5\u4f7f\u5176\u5728 stackoverflow \u4e0a\u66f4\u5177\u53ef\u8bfb\u6027\u3002<\/p>\n<p>\u56e0\u6b64\uff0c\u5f53\u6211\u83b7\u53d6 <code>location<\/code> \u7684\u5185\u5bb9\u5e76\u5c1d\u8bd5\u4f7f\u7528 <code>ioutil.readall()<\/code> \u5904\u7406\u6570\u636e\u65f6\uff0c\u6211\u6536\u5230\u6b64\u9519\u8bef\uff0c\u5176\u4e2d\u63d0\u5230\u4e86\u4e00\u4e2a\u6307\u9488\uff1a<\/p>\n<pre>panic: runtime error: invalid memory address or nil pointer dereference\n[signal sigsegv: segmentation violation code=0x1 addr=0x40 pc=0x1210a69]\n\ngoroutine 1 [running]:\nmain.main()\n    \/users\/tom\/developer\/go\/src\/news\/index.go:23 +0x159\nexit status 2<\/pre>\n<p>\u65e0\u8bba\u6211\u5982\u4f55\u7814\u7a76\u5b83\uff0c\u6211\u771f\u7684\u4e0d\u660e\u767d\u8fd9\u4e2a\u9519\u8bef\u3002\u6211\u5c1d\u8bd5\u901a\u8fc7\u6267\u884c <code>_, e := ioutil.readall(resp.body)<\/code> \u7136\u540e\u6253\u5370 <code>e<\/code> \u4ece <code>ioutil.readall(resp.body)<\/code> \u4e2d\u63d0\u53d6\u9519\u8bef\uff0c\u4f46\u8fd9\u6837\u505a\u4f1a\u5f15\u53d1\u53e6\u4e00\u4e2a\u9519\u8bef&#8230;<\/p>\n<p>\u6211\u5728\u67d0\u5904\u8bfb\u5230\u8fd9\u53ef\u80fd\u662f\u56e0\u4e3a\u8fd4\u56de\u7ed9\u6211\u7684\u6b63\u6587\u6709\u9519\u8bef\uff0c\u4f46\u5b83\u5728\u6559\u7a0b\u4e2d\u5de5\u4f5c\u6b63\u5e38\u3002<\/p>\n<p>\u5e0c\u671b\u4f60\u4eec\u80fd\u7ed9\u6211\u4e00\u4e2a\u89e3\u51b3\u65b9\u6848\u3002\u8c22\u8c22\u3002<\/p>\n<p>\u7f16\u8f91\uff1a\u8fd9\u662f\u6211\u5b9a\u4e49\u7684\u7ed3\u6784\uff1a<\/p>\n<pre>type SitemapIndex struct {\n    Locations []string `xml:\"sitemap&gt;loc\"`\n}\n\ntype News struct {\n    Titles []string `xml:\"url&gt;news&gt;title\"`\n    Keywords []string `xml:\"url&gt;news&gt;keywords\"`\n    Locations []string `xml:\"url&gt;loc\"`\n}\n\ntype NewsMap struct {\n    Keyword string\n    Location string\n}<\/pre>\n<p> <\/p>\n<h2>\u89e3\u51b3\u65b9\u6848<\/h2>\n<p> <\/p>\n<p>\u597d\u7684\uff0c\u6211\u5df2\u7ecf\u627e\u5230\u95ee\u9898\u7684\u539f\u56e0\u4ee5\u53ca\u89e3\u51b3\u65b9\u6cd5\u4e86\u3002\u95ee\u9898\u662f\u8be5\u7f51\u5740\u6709\u4e00\u4e9b\u6211\u6ca1\u6709\u770b\u5230\u7684\u6362\u884c\u7b26\u3002<\/p>\n<p>\u6240\u4ee5\u4e0d\u8981\u8fd9\u6837\u505a\uff1a<\/p>\n<pre>resp, err := http.get(location)<\/pre>\n<p>\u6211\u8fd9\u6837\u505a\u4e86\uff1a<\/p>\n<pre>resp, err := http.get(strings.trimspace(location))<\/pre>\n<p>\u89e3\u51b3\u4e86\u8fd9\u4e2a\u95ee\u9898\u3002<\/p>\n<p><strong>go \u7684\u7b2c\u4e00\u6761\u89c4\u5219\uff1a\u68c0\u67e5\u9519\u8bef\u3002<\/strong><\/p>\n<p>\u4f8b\u5982\uff0c<\/p>\n<pre>if err != nil {\n    fmt.printf(\"%q\\n\", location) \/\/ debug error\n    fmt.println(resp)            \/\/ debug error\n    fmt.println(err)\n    return\n}<\/pre>\n<p>\u8f93\u51fa\uff1a<\/p>\n<pre>\"\\nhttps:\/\/www.washingtonpost.com\/news-sitemaps\/politics.xml\\n\"\n&lt;nil&gt;\nparse \nhttps:\/\/www.washingtonpost.com\/news-sitemaps\/politics.xml\n: first path segment in url cannot contain colon<\/pre>\n<p>\u5982\u679c\u60a8\u6ca1\u6709\u53d1\u73b0\u6b64\u9519\u8bef\u5e76\u7ee7\u7eed\u4f7f\u7528 <code>resp == nil<\/code> \u5219<\/p>\n<pre>bytes, err := ioutil.readall(resp.body)<\/pre>\n<p>\u8f93\u51fa\uff1a<\/p>\n<pre>panic: runtime error: invalid memory address or nil pointer dereference<\/pre>\n<pre>package main\n\nimport (\n    \"encoding\/xml\"\n    \"fmt\"\n    \"io\/ioutil\"\n    \"net\/http\"\n    \"strings\"\n)\n\ntype SitemapIndex struct {\n    Locations []string `xml:\"sitemap&gt;loc\"`\n}\n\nfunc main() {\n    var s SitemapIndex\n\n    resp, err := http.Get(\"https:\/\/www.washingtonpost.com\/news-sitemaps\/index.xml\")\n    if err != nil {\n        fmt.Println(err)\n        return\n    }\n    bytes, err := ioutil.ReadAll(resp.Body)\n    if err != nil {\n        fmt.Println(err)\n        return\n    }\n    err = resp.Body.Close()\n    if err != nil {\n        fmt.Println(err)\n        return\n    }\n\n    err = xml.Unmarshal(bytes, &amp;s)\n    if err != nil {\n        fmt.Println(err)\n        return\n    }\n\n    for _, Location := range s.Locations {\n        resp, err := http.Get(Location)\n        if err != nil {\n            fmt.Printf(\"%q\\n\", Location) \/\/ debug error\n            fmt.Println(resp)            \/\/ debug error\n            fmt.Println(err)\n            return\n        }\n        bytes, err := ioutil.ReadAll(resp.Body)\n        if err != nil {\n            fmt.Println(err)\n            return\n        }\n        fmt.Println(len(bytes))\n        err = resp.Body.Close()\n        if err != nil {\n            fmt.Println(err)\n            return\n        }\n    }\n}<\/pre>\n<p>\u672c\u7bc7\u5173\u4e8e\u300aGolang \u4e2d\u4f7f\u7528 ioutil.ReadAll() \u51fa\u73b0\u201c\u65e0\u6548\u5185\u5b58\u5730\u5740\u201d\u300b\u7684\u4ecb\u7ecd\u5c31\u5230\u6b64\u7ed3\u675f\u5566\uff0c\u4f46\u662f\u5b66\u65e0\u6b62\u5883\uff0c\u60f3\u8981\u4e86\u89e3\u5b66\u4e60\u66f4\u591a\u5173\u4e8eGolang\u7684\u76f8\u5173\u77e5\u8bc6\uff0c\u8bf7\u5173\u6ce8\u516c\u4f17\u53f7\uff01<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5f53\u524d\u4f4d\u7f6e\uff1a &gt; &gt; &#46;&#46;&#46;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4925],"tags":[],"class_list":["post-208108","post","type-post","status-publish","format-standard","hentry","category-4925"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/208108","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"}],"author":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/comments?post=208108"}],"version-history":[{"count":0,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/208108\/revisions"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=208108"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=208108"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=208108"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}