100162744.htm
来自「C#高级编程(第三版),顶死你们。。 。up」· HTM 代码 · 共 86 行
HTM
86 行
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head><title>
2.7 数组
</title></head>
<body>
<div class="area">
<div class="col1">
<div class="lineBlue">
</div>
<!-- title -->
<div class="arcTitle">
<h1>
<a href="../16">
C#高级编程(第3版)【全文连载】
</a>
</h1>
<div style="text-align: center; font-size: 15px">
<a href="100162744.htm">
2.7 数组
</a>
</div>
<div style="text-align: center; font-size: 15px">
<a class="url" href="../../default.htm">http://book.csdn.net/</a>
2006-8-17 16:57:00
</div>
<div style="margin: 0px auto; width: 700px; border: solid 1px #0b5f98;">
<div style="float: left; width: 16px; background-color: #0b5f98; color: White; padding: 1px;">
图书导读
</div>
<div style="float: right; width: 670px; text-align: left; line-height: 16pt; padding-left: 2px">
<!--导读-->
<h1 id="divCurrentNode" style="color: #b83507; width: 100%; text-align: left; font-size: 12px; padding-left: 2px">当前章节:<a href='100162744.htm'><font color='red'>2.7 数组</font></a></h1>
<div id="divRelateNode" style="padding-left: 2px">
<div style='float:left;width:49%'>·<a href='100162741.htm'>2.4 预定义数据类型</a></div><div style='float:right;width:49%'>·<a href='100162742.htm'>2.5 流控制</a></div><div style='float:left;width:49%'>·<a href='100162743.htm'>2.6 枚举</a></div><div style='float:right;width:49%'>·<a href='100162745.htm'>2.8 命名空间</a></div><div style='float:left;width:49%'>·<a href='100162746.htm'>2.9 Main()方法</a></div><div style='float:right;width:49%'>·<a href='100162747.htm'>2.10 有关编译C#文件的更多内容</a></div></div>
</div>
</div>
</div>
<!-- main -->
<div id="main">
<div id="text"> <link href="css.css" rel="stylesheet" type="text/css" /><p class="MsoNormal"><span><span style="FONT-FAMILY: 宋体">本章不打算详细介绍数组,因为第</span><span lang="EN-US">9</span></span><span style="FONT-FAMILY: 宋体">章将详细论述数组和集合。但本章将介绍编写一维数组的语法。在声明</span><span lang="EN-US">C#</span><span style="FONT-FAMILY: 宋体">中的数组时,要在各个元素的变量类型后面,加上一组方括号</span><span lang="EN-US">(</span><span style="FONT-FAMILY: 宋体">注意数组中的所有元素必须有相同的数据类型</span><span lang="EN-US">)</span><span style="FONT-FAMILY: 宋体">。</span></p>
<p class="a3" style="MARGIN-TOP: 8.15pt; TEXT-INDENT: 21.45pt"><span style="FONT-FAMILY: 黑体">提示:</span></p>
<p class="a1" style="MARGIN-BOTTOM: 8.15pt; TEXT-INDENT: 21.45pt"><span lang="EN-US">VB</span><span style="FONT-FAMILY: 楷体_GB2312">用户注意,</span><span lang="EN-US">C#</span><span style="FONT-FAMILY: 楷体_GB2312">中的数组使用方括号,而不是圆括号。</span><span lang="EN-US">C++</span><span style="FONT-FAMILY: 楷体_GB2312">用户很熟悉方括号,但应仔细查看这里给出的代码,因为声明数组变量的</span><span lang="EN-US">C#</span><span style="FONT-FAMILY: 楷体_GB2312">语法与</span><span lang="EN-US">C++</span><span style="FONT-FAMILY: 楷体_GB2312">语法并不相同。</span></p>
<p class="MsoNormal"><span style="FONT-FAMILY: 宋体">例如,</span><span lang="EN-US">int</span><span style="FONT-FAMILY: 宋体">表示一个整数,而</span><span lang="EN-US">int[]</span><span style="FONT-FAMILY: 宋体">表示一个整型数组:</span></p>
<p class="2" style="MARGIN: 8.15pt 0cm 8.15pt 21.45pt; TEXT-INDENT: 18.45pt"><span lang="EN-US">int[] integers;</span></p>
<p class="MsoNormal"><span style="FONT-FAMILY: 宋体">要初始化特定大小的数组,可以使用</span><span lang="EN-US">new</span><span style="FONT-FAMILY: 宋体">关键字,在类型名后面的方括号中给出大小:</span></p>
<p class="2" style="MARGIN: 8.15pt 0cm 0pt 21.45pt; TEXT-INDENT: 18.45pt"><span lang="EN-US">// Create a new array of 32 ints</span></p>
<p class="2" style="MARGIN: 0cm 0cm 8.15pt 21.45pt; TEXT-INDENT: 18.45pt"><span lang="EN-US">int[] integers = new int[32];</span></p>
<p class="MsoNormal"><span style="FONT-FAMILY: 宋体">所有的数组都是引用类型,并遵循引用的语义。因此,即使各个元素都是基本的值类型,</span><span lang="EN-US">integers</span><span style="FONT-FAMILY: 宋体">数组也是引用类型。如果以后编写如下代码:</span></p>
<p class="2" style="MARGIN: 8.15pt 0cm 8.15pt 21.45pt; TEXT-INDENT: 18.45pt"><span lang="EN-US">int[] copy = integers;</span></p>
<p class="MsoNormal"><span style="FONT-FAMILY: 宋体">该代码也只是把变量</span><span lang="EN-US">copy</span><span style="FONT-FAMILY: 宋体">指向同一个数组,而不是创建一个新数组。</span></p>
<p class="MsoNormal"><span style="FONT-FAMILY: 宋体">要访问数组中的单个元素,可以使用通常的语法,在数组名的后面,把元素的下标放在方括号中。所有的</span><span lang="EN-US">C#</span><span style="FONT-FAMILY: 宋体">数组都使用基于</span><span lang="EN-US">0</span><span style="FONT-FAMILY: 宋体">的下标方式,所以要用下标</span><span lang="EN-US">0</span><span style="FONT-FAMILY: 宋体">引用第一个变量:</span></p>
<p class="2" style="MARGIN: 8.15pt 0cm 8.15pt 21.45pt; TEXT-INDENT: 18.45pt"><span lang="EN-US">integers[0] = 35;</span></p>
<p class="MsoNormal"><span style="FONT-FAMILY: 宋体">同样,用下标值</span><span lang="EN-US">31</span><span style="FONT-FAMILY: 宋体">引用有</span><span lang="EN-US">32</span><span style="FONT-FAMILY: 宋体">个元素的数组中的最后一个元素:</span></p>
<p class="2" style="MARGIN: 8.15pt 0cm 8.15pt 21.45pt; TEXT-INDENT: 18.45pt"><span lang="EN-US">integers[31] = 432;</span></p>
<p class="MsoNormal"><span lang="EN-US">C#</span><span style="FONT-FAMILY: 宋体">的数组语法也非常灵活,实际上,</span><span lang="EN-US">C#</span><span style="FONT-FAMILY: 宋体">可以在声明数组时不进行初始化,这样以后就可以在程序中动态地指定其大小。利用这项技术,可以创建一个空引用,以后再使用</span><span lang="EN-US">new</span><span style="FONT-FAMILY: 宋体">关键字把这个引用指向请求动态分配的内存位置:</span></p>
<p class="2" style="MARGIN: 8.15pt 0cm 0pt 21.45pt; TEXT-INDENT: 18.45pt"><span lang="EN-US">int[] integers;</span></p>
<p class="2" style="MARGIN: 0cm 0cm 8.15pt 21.45pt; TEXT-INDENT: 18.45pt"><span lang="EN-US">integers = new int[32];</span></p>
<p class="MsoNormal"><span style="FONT-FAMILY: 宋体">可以使用下面的语法查看一个数组包含多少个元素:</span></p>
<p class="a6" style="MARGIN: 8.15pt 0cm 8.15pt 21.45pt; TEXT-INDENT: 18.45pt"><span lang="EN-US">int numElements = integers.Length; // integers is any reference to an array</span></p></div>
<!-- page -->
<div class="page" style="text-align: center">
<a href="100162743.htm">上一页</a> <a href="index.html">首页</a> <a href="100162745.htm">下一页</a>
</div>
<div style="margin: 0px auto; width: 700px; border: solid 1px #0b5f98;">
<div style="float: left; width: 16px; background-color: #0b5f98; color: White; padding: 1px;">
图书导读
</div>
<div style="float: right; width: 670px; text-align: left; line-height: 16pt; padding-left: 2px">
<!--导读-->
<h1 id="divCurrentNode2" style="color: #b83507; width: 100%; text-align: left; font-size: 12px; padding-left: 2px">当前章节:<a href='100162744.htm'><font color='red'>2.7 数组</font></a></h1>
<div id="divRealteNod2" style="padding-left: 2px">
<div style='float:left;width:49%'>·<a href='100162741.htm'>2.4 预定义数据类型</a></div><div style='float:right;width:49%'>·<a href='100162742.htm'>2.5 流控制</a></div><div style='float:left;width:49%'>·<a href='100162743.htm'>2.6 枚举</a></div><div style='float:right;width:49%'>·<a href='100162745.htm'>2.8 命名空间</a></div><div style='float:left;width:49%'>·<a href='100162746.htm'>2.9 Main()方法</a></div><div style='float:right;width:49%'>·<a href='100162747.htm'>2.10 有关编译C#文件的更多内容</a></div></div>
</div>
</div>
</div>
</div>
</body>
</html>
⌨️ 快捷键说明
复制代码Ctrl + C
搜索代码Ctrl + F
全屏模式F11
增大字号Ctrl + =
减小字号Ctrl + -
显示快捷键?