mirror of
https://github.com/gopl-zh/gopl-zh.github.com.git
synced 2024-11-24 15:18:57 +00:00
271 lines
29 KiB
HTML
271 lines
29 KiB
HTML
|
<!DOCTYPE HTML>
|
|||
|
|
<html lang="zh" class="sidebar-visible no-js light">
|
|||
|
|
<head>
|
|||
|
|
<!-- Book generated using mdBook -->
|
|||
|
|
<meta charset="UTF-8">
|
|||
|
|
<title>显示一个类型的方法集 - Go语言圣经</title>
|
|||
|
|
|
|||
|
|
|
|||
|
|
<!-- Custom HTML head -->
|
|||
|
|
|
|||
|
|
|
|||
|
|
<meta content="text/html; charset=utf-8" http-equiv="Content-Type">
|
|||
|
|
<meta name="description" content="<The Go Programming Language>中文版">
|
|||
|
|
<meta name="viewport" content="width=device-width, initial-scale=1">
|
|||
|
|
<meta name="theme-color" content="#ffffff" />
|
|||
|
|
|
|||
|
|
<link rel="icon" href="../favicon.svg">
|
|||
|
|
<link rel="shortcut icon" href="../favicon.png">
|
|||
|
|
<link rel="stylesheet" href="../css/variables.css">
|
|||
|
|
<link rel="stylesheet" href="../css/general.css">
|
|||
|
|
<link rel="stylesheet" href="../css/chrome.css">
|
|||
|
|
<link rel="stylesheet" href="../css/print.css" media="print">
|
|||
|
|
|
|||
|
|
<!-- Fonts -->
|
|||
|
|
<link rel="stylesheet" href="../FontAwesome/css/font-awesome.css">
|
|||
|
|
<link rel="stylesheet" href="../fonts/fonts.css">
|
|||
|
|
|
|||
|
|
<!-- Highlight.js Stylesheets -->
|
|||
|
|
<link rel="stylesheet" href="../highlight.css">
|
|||
|
|
<link rel="stylesheet" href="../tomorrow-night.css">
|
|||
|
|
<link rel="stylesheet" href="../ayu-highlight.css">
|
|||
|
|
|
|||
|
|
<!-- Custom theme stylesheets -->
|
|||
|
|
<link rel="stylesheet" href="../style.css">
|
|||
|
|
|
|||
|
|
|
|||
|
|
</head>
|
|||
|
|
<body>
|
|||
|
|
<!-- Provide site root to javascript -->
|
|||
|
|
<script type="text/javascript">
|
|||
|
|
var path_to_root = "../";
|
|||
|
|
var default_theme = window.matchMedia("(prefers-color-scheme: dark)").matches ? "navy" : "light";
|
|||
|
|
</script>
|
|||
|
|
|
|||
|
|
<!-- Work around some values being stored in localStorage wrapped in quotes -->
|
|||
|
|
<script type="text/javascript">
|
|||
|
|
try {
|
|||
|
|
var theme = localStorage.getItem('mdbook-theme');
|
|||
|
|
var sidebar = localStorage.getItem('mdbook-sidebar');
|
|||
|
|
|
|||
|
|
if (theme.startsWith('"') && theme.endsWith('"')) {
|
|||
|
|
localStorage.setItem('mdbook-theme', theme.slice(1, theme.length - 1));
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
if (sidebar.startsWith('"') && sidebar.endsWith('"')) {
|
|||
|
|
localStorage.setItem('mdbook-sidebar', sidebar.slice(1, sidebar.length - 1));
|
|||
|
|
}
|
|||
|
|
} catch (e) { }
|
|||
|
|
</script>
|
|||
|
|
|
|||
|
|
<!-- Set the theme before any content is loaded, prevents flash -->
|
|||
|
|
<script type="text/javascript">
|
|||
|
|
var theme;
|
|||
|
|
try { theme = localStorage.getItem('mdbook-theme'); } catch(e) { }
|
|||
|
|
if (theme === null || theme === undefined) { theme = default_theme; }
|
|||
|
|
var html = document.querySelector('html');
|
|||
|
|
html.classList.remove('no-js')
|
|||
|
|
html.classList.remove('light')
|
|||
|
|
html.classList.add(theme);
|
|||
|
|
html.classList.add('js');
|
|||
|
|
</script>
|
|||
|
|
|
|||
|
|
<!-- Hide / unhide sidebar before it is displayed -->
|
|||
|
|
<script type="text/javascript">
|
|||
|
|
var html = document.querySelector('html');
|
|||
|
|
var sidebar = 'hidden';
|
|||
|
|
if (document.body.clientWidth >= 1080) {
|
|||
|
|
try { sidebar = localStorage.getItem('mdbook-sidebar'); } catch(e) { }
|
|||
|
|
sidebar = sidebar || 'visible';
|
|||
|
|
}
|
|||
|
|
html.classList.remove('sidebar-visible');
|
|||
|
|
html.classList.add("sidebar-" + sidebar);
|
|||
|
|
</script>
|
|||
|
|
|
|||
|
|
<nav id="sidebar" class="sidebar" aria-label="Table of contents">
|
|||
|
|
<div class="sidebar-scrollbox">
|
|||
|
|
<ol class="chapter"><li class="chapter-item expanded affix "><a href="../index.html">Go语言圣经</a></li><li class="chapter-item expanded affix "><a href="../preface.html">前言</a></li><li class="chapter-item expanded "><a href="../ch1/ch1.html"><strong aria-hidden="true">1.</strong> 入门</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../ch1/ch1-01.html"><strong aria-hidden="true">1.1.</strong> Hello, World</a></li><li class="chapter-item expanded "><a href="../ch1/ch1-02.html"><strong aria-hidden="true">1.2.</strong> 命令行参数</a></li><li class="chapter-item expanded "><a href="../ch1/ch1-03.html"><strong aria-hidden="true">1.3.</strong> 查找重复的行</a></li><li class="chapter-item expanded "><a href="../ch1/ch1-04.html"><strong aria-hidden="true">1.4.</strong> GIF动画</a></li><li class="chapter-item expanded "><a href="../ch1/ch1-05.html"><strong aria-hidden="true">1.5.</strong> 获取URL</a></li><li class="chapter-item expanded "><a href="../ch1/ch1-06.html"><strong aria-hidden="true">1.6.</strong> 并发获取多个URL</a></li><li class="chapter-item expanded "><a href="../ch1/ch1-07.html"><strong aria-hidden="true">1.7.</strong> Web服务</a></li><li class="chapter-item expanded "><a href="../ch1/ch1-08.html"><strong aria-hidden="true">1.8.</strong> 本章要点</a></li></ol></li><li class="chapter-item expanded "><a href="../ch2/ch2.html"><strong aria-hidden="true">2.</strong> 程序结构</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../ch2/ch2-01.html"><strong aria-hidden="true">2.1.</strong> 命名</a></li><li class="chapter-item expanded "><a href="../ch2/ch2-02.html"><strong aria-hidden="true">2.2.</strong> 声明</a></li><li class="chapter-item expanded "><a href="../ch2/ch2-03.html"><strong aria-hidden="true">2.3.</strong> 变量</a></li><li class="chapter-item expanded "><a href="../ch2/ch2-04.html"><strong aria-hidden="true">2.4.</strong> 赋值</a></li><li class="chapter-item expanded "><a href="../ch2/ch2-05.html"><strong aria-hidden="true">2.5.</strong> 类型</a></li><li class="chapter-item expanded "><a href="../ch2/ch2-06.html"><strong aria-hidden="true">2.6.</strong> 包和文件</a></li><li class="chapter-item expanded "><a href="../ch2/ch2-07.html"><strong aria-hidden="true">2.7.</strong> 作用域</a></li></ol></li><li class="chapter-item expanded "><a href="../ch3/ch3.html"><strong aria-hidden="true">3.</strong> 基础数据类型</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../ch3/ch3-01.html"><strong aria-hidden="true">3.1.</strong> 整型</a></li><li class="chapter-item expanded "><a href="../ch3/ch3-02.html"><strong aria-hidden="true">3.2.</strong> 浮点数</a></li><li class="chapter-item expanded "><a href="../ch3/ch3-03.html"><strong aria-hidden="true">3.3.</strong> 复数</a></li><li class="chapter-item expanded "><a href="../ch3/ch3-04.html"><strong aria-hidden="true">3.4.</strong> 布尔型</a></li><li class="chapter-item expanded "><a href="../ch3/ch3-05.html"><strong aria-hidden="true">3.5.</strong> 字符串</a></li><li class="chapter-item expanded "><a href="../ch3/ch3-06.html"><strong aria-hidden="true">3.6.</strong> 常量</a></li></ol></li><li class="chapter-item expanded "><a href="../ch4/ch4.html"><strong aria-hidden="true">4.</strong> 复合数据类型</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../ch4/ch4-01.html"><strong aria-hidden="true">4.1.</strong> 数组</a></li><li class="chapter-item expanded "><a href="../ch4/ch4-02.html"><strong aria-hidden="true">4.2.</strong> Slice</a></li><li class="chapter-item expanded "><a href="../ch4/ch4-03.html"><strong aria-hidden="true">4.3.</strong> Map</a></li><li class="chapter-item expanded "><a href="../ch4/ch4-04.html"><strong aria-hidden="true">4.4.</strong> 结构体</a></li><li class="chapter-item expanded "><a href="../ch4/ch4-05.html"><strong aria-hidden="true">4.5.</strong> JSON</a></li><li class="chapter-item expanded "><a href="../ch4/ch4-06.html"><strong aria-hidd
|
|||
|
|
<div id="sidebar-resize-handle" class="sidebar-resize-handle"></div>
|
|||
|
|
</nav>
|
|||
|
|
|
|||
|
|
<div id="page-wrapper" class="page-wrapper">
|
|||
|
|
|
|||
|
|
<div class="page">
|
|||
|
|
|
|||
|
|
<div id="menu-bar-hover-placeholder"></div>
|
|||
|
|
<div id="menu-bar" class="menu-bar sticky bordered">
|
|||
|
|
<div class="left-buttons">
|
|||
|
|
<button id="sidebar-toggle" class="icon-button" type="button" title="Toggle Table of Contents" aria-label="Toggle Table of Contents" aria-controls="sidebar">
|
|||
|
|
<i class="fa fa-bars"></i>
|
|||
|
|
</button>
|
|||
|
|
<button id="theme-toggle" class="icon-button" type="button" title="Change theme" aria-label="Change theme" aria-haspopup="true" aria-expanded="false" aria-controls="theme-list">
|
|||
|
|
<i class="fa fa-paint-brush"></i>
|
|||
|
|
</button>
|
|||
|
|
<ul id="theme-list" class="theme-popup" aria-label="Themes" role="menu">
|
|||
|
|
<li role="none"><button role="menuitem" class="theme" id="light">Light (default)</button></li>
|
|||
|
|
<li role="none"><button role="menuitem" class="theme" id="rust">Rust</button></li>
|
|||
|
|
<li role="none"><button role="menuitem" class="theme" id="coal">Coal</button></li>
|
|||
|
|
<li role="none"><button role="menuitem" class="theme" id="navy">Navy</button></li>
|
|||
|
|
<li role="none"><button role="menuitem" class="theme" id="ayu">Ayu</button></li>
|
|||
|
|
</ul>
|
|||
|
|
<button id="search-toggle" class="icon-button" type="button" title="Search. (Shortkey: s)" aria-label="Toggle Searchbar" aria-expanded="false" aria-keyshortcuts="S" aria-controls="searchbar">
|
|||
|
|
<i class="fa fa-search"></i>
|
|||
|
|
</button>
|
|||
|
|
</div>
|
|||
|
|
|
|||
|
|
<h1 class="menu-title">Go语言圣经</h1>
|
|||
|
|
|
|||
|
|
<div class="right-buttons">
|
|||
|
|
<a href="../print.html" title="Print this book" aria-label="Print this book">
|
|||
|
|
<i id="print-button" class="fa fa-print"></i>
|
|||
|
|
</a>
|
|||
|
|
<a href="https://github.com/gopl-zh/gopl-zh.github.com" title="Git repository" aria-label="Git repository">
|
|||
|
|
<i id="git-repository-button" class="fa fa-github"></i>
|
|||
|
|
</a>
|
|||
|
|
<a href="https://github.com/gopl-zh/gopl-zh.github.com/edit/master/./ch12/ch12-08.md" title="Suggest an edit" aria-label="Suggest an edit">
|
|||
|
|
<i id="git-edit-button" class="fa fa-edit"></i>
|
|||
|
|
</a>
|
|||
|
|
|
|||
|
|
</div>
|
|||
|
|
</div>
|
|||
|
|
|
|||
|
|
<div id="search-wrapper" class="hidden">
|
|||
|
|
<form id="searchbar-outer" class="searchbar-outer">
|
|||
|
|
<input type="search" id="searchbar" name="searchbar" placeholder="Search this book ..." aria-controls="searchresults-outer" aria-describedby="searchresults-header">
|
|||
|
|
</form>
|
|||
|
|
<div id="searchresults-outer" class="searchresults-outer hidden">
|
|||
|
|
<div id="searchresults-header" class="searchresults-header"></div>
|
|||
|
|
<ul id="searchresults">
|
|||
|
|
</ul>
|
|||
|
|
</div>
|
|||
|
|
</div>
|
|||
|
|
|
|||
|
|
<!-- Apply ARIA attributes after the sidebar and the sidebar toggle button are added to the DOM -->
|
|||
|
|
<script type="text/javascript">
|
|||
|
|
document.getElementById('sidebar-toggle').setAttribute('aria-expanded', sidebar === 'visible');
|
|||
|
|
document.getElementById('sidebar').setAttribute('aria-hidden', sidebar !== 'visible');
|
|||
|
|
Array.from(document.querySelectorAll('#sidebar a')).forEach(function(link) {
|
|||
|
|
link.setAttribute('tabIndex', sidebar === 'visible' ? 0 : -1);
|
|||
|
|
});
|
|||
|
|
</script>
|
|||
|
|
|
|||
|
|
<div id="content" class="content">
|
|||
|
|
<!-- Page table of contents -->
|
|||
|
|
<div class="sidetoc"><nav class="pagetoc"></nav></div>
|
|||
|
|
<main>
|
|||
|
|
<!-- 头部 -->
|
|||
|
|
<ul dir="auto">
|
|||
|
|
<li><em>KusonStack一站式可编程配置技术栈: <a href="https://github.com/KusionStack/kusion">https://github.com/KusionStack/kusion</a></em></li>
|
|||
|
|
<li><em>凹语言™: <a href="https://github.com/wa-lang/wa">https://github.com/wa-lang/wa</a></em></li>
|
|||
|
|
</ul>
|
|||
|
|
<hr>
|
|||
|
|
|
|||
|
|
<h2 id="128-显示一个类型的方法集"><a class="header" href="#128-显示一个类型的方法集">12.8. 显示一个类型的方法集</a></h2>
|
|||
|
|
<p>我们的最后一个例子是使用reflect.Type来打印任意值的类型和枚举它的方法：</p>
|
|||
|
|
<p><u><i>gopl.io/ch12/methods</i></u></p>
|
|||
|
|
<pre><code class="language-Go">// Print prints the method set of the value x.
|
|||
|
|
func Print(x interface{}) {
|
|||
|
|
v := reflect.ValueOf(x)
|
|||
|
|
t := v.Type()
|
|||
|
|
fmt.Printf("type %s\n", t)
|
|||
|
|
|
|||
|
|
for i := 0; i < v.NumMethod(); i++ {
|
|||
|
|
methType := v.Method(i).Type()
|
|||
|
|
fmt.Printf("func (%s) %s%s\n", t, t.Method(i).Name,
|
|||
|
|
strings.TrimPrefix(methType.String(), "func"))
|
|||
|
|
}
|
|||
|
|
}
|
|||
|
|
</code></pre>
|
|||
|
|
<p>reflect.Type和reflect.Value都提供了一个Method方法。每次t.Method(i)调用将一个reflect.Method的实例，对应一个用于描述一个方法的名称和类型的结构体。每次v.Method(i)方法调用都返回一个reflect.Value以表示对应的值（§6.4），也就是一个方法是绑到它的接收者的。使用reflect.Value.Call方法（我们这里没有演示），将可以调用一个Func类型的Value，但是这个例子中只用到了它的类型。</p>
|
|||
|
|
<p>这是属于time.Duration和<code>*strings.Replacer</code>两个类型的方法：</p>
|
|||
|
|
<pre><code class="language-Go">methods.Print(time.Hour)
|
|||
|
|
// Output:
|
|||
|
|
// type time.Duration
|
|||
|
|
// func (time.Duration) Hours() float64
|
|||
|
|
// func (time.Duration) Minutes() float64
|
|||
|
|
// func (time.Duration) Nanoseconds() int64
|
|||
|
|
// func (time.Duration) Seconds() float64
|
|||
|
|
// func (time.Duration) String() string
|
|||
|
|
|
|||
|
|
methods.Print(new(strings.Replacer))
|
|||
|
|
// Output:
|
|||
|
|
// type *strings.Replacer
|
|||
|
|
// func (*strings.Replacer) Replace(string) string
|
|||
|
|
// func (*strings.Replacer) WriteString(io.Writer, string) (int, error)
|
|||
|
|
</code></pre>
|
|||
|
|
|
|||
|
|
|
|||
|
|
<!-- 公众号 -->
|
|||
|
|
<hr>
|
|||
|
|
<table>
|
|||
|
|
<tr>
|
|||
|
|
<td>
|
|||
|
|
<img width="222px" src="https://chai2010.cn/advanced-go-programming-book/css.png">
|
|||
|
|
</td>
|
|||
|
|
<td>
|
|||
|
|
<img width="222px" src="https://chai2010.cn/advanced-go-programming-book/cch.png">
|
|||
|
|
</td>
|
|||
|
|
</tr>
|
|||
|
|
</table>
|
|||
|
|
|
|||
|
|
<div id="giscus-container"></div>
|
|||
|
|
<footer class="page-footer">
|
|||
|
|
<span>© 2015-2016 | <a href="https://github.com/gopl-zh"> Go语言圣经中文版</a>, 仅学习交流使用</span>
|
|||
|
|
</footer>
|
|||
|
|
</main>
|
|||
|
|
|
|||
|
|
<nav class="nav-wrapper" aria-label="Page navigation">
|
|||
|
|
<!-- Mobile navigation buttons -->
|
|||
|
|
<a rel="prev" href="../ch12/ch12-06.html" class="mobile-nav-chapters previous" title="Previous chapter" aria-label="Previous chapter" aria-keyshortcuts="Left">
|
|||
|
|
<i class="fa fa-angle-left"></i>
|
|||
|
|
</a>
|
|||
|
|
|
|||
|
|
<a rel="next" href="../ch12/ch12-09.html" class="mobile-nav-chapters next" title="Next chapter" aria-label="Next chapter" aria-keyshortcuts="Right">
|
|||
|
|
<i class="fa fa-angle-right"></i>
|
|||
|
|
</a>
|
|||
|
|
|
|||
|
|
<div style="clear: both"></div>
|
|||
|
|
</nav>
|
|||
|
|
</div>
|
|||
|
|
</div>
|
|||
|
|
|
|||
|
|
<nav class="nav-wide-wrapper" aria-label="Page navigation">
|
|||
|
|
<a rel="prev" href="../ch12/ch12-06.html" class="nav-chapters previous" title="Previous chapter" aria-label="Previous chapter" aria-keyshortcuts="Left">
|
|||
|
|
<i class="fa fa-angle-left"></i>
|
|||
|
|
</a>
|
|||
|
|
|
|||
|
|
<a rel="next" href="../ch12/ch12-09.html" class="nav-chapters next" title="Next chapter" aria-label="Next chapter" aria-keyshortcuts="Right">
|
|||
|
|
<i class="fa fa-angle-right"></i>
|
|||
|
|
</a>
|
|||
|
|
</nav>
|
|||
|
|
|
|||
|
|
</div>
|
|||
|
|
|
|||
|
|
|
|||
|
|
|
|||
|
|
|
|||
|
|
<script type="text/javascript">
|
|||
|
|
window.playground_copyable = true;
|
|||
|
|
</script>
|
|||
|
|
|
|||
|
|
|
|||
|
|
<script src="../elasticlunr.min.js" type="text/javascript" charset="utf-8"></script>
|
|||
|
|
<script src="../mark.min.js" type="text/javascript" charset="utf-8"></script>
|
|||
|
|
<script src="../searcher.js" type="text/javascript" charset="utf-8"></script>
|
|||
|
|
|
|||
|
|
<script src="../clipboard.min.js" type="text/javascript" charset="utf-8"></script>
|
|||
|
|
<script src="../highlight.js" type="text/javascript" charset="utf-8"></script>
|
|||
|
|
<script src="../book.js" type="text/javascript" charset="utf-8"></script>
|
|||
|
|
<script type="text/javascript" charset="utf-8">
|
|||
|
|
var pagePath = "ch12/ch12-08.md"
|
|||
|
|
</script>
|
|||
|
|
|
|||
|
|
|
|||
|
|
<!-- Custom JS scripts -->
|
|||
|
|
<script type="text/javascript" src="../js/custom.js"></script>
|
|||
|
|
<script type="text/javascript" src="../js/bigPicture.js"></script>
|
|||
|
|
|
|||
|
|
|
|||
|
|
</body>
|
|||
|
|
</html>
|