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            <p class="a4" style="MARGIN-LEFT: 2.05pt; TEXT-INDENT: 5.35pt"><span lang="EN-US">decimal</span></p>
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            <p class="a4" style="MARGIN-LEFT: 10.7pt"><span lang="EN-US">System.<br />Decimal</span></p>
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            <p class="a4" style="MARGIN-LEFT: 10.7pt"><span lang="EN-US">128</span><span style="FONT-FAMILY: 宋体">位高精度十进制数表示法</span></p>
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            <p class="a4" style="MARGIN-LEFT: 0cm; TEXT-ALIGN: center" align="center"><span lang="EN-US">28</span></p>
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            <p class="a4" style="MARGIN-LEFT: 10.7pt"><span lang="EN-US">&plusmn;1.0&times;10<sup>-28</sup></span><span style="FONT-FAMILY: 宋体">到</span><span lang="EN-US">&plusmn;7.9 &times; 10<sup>28</sup></span></p>
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<p class="MsoNormal"><span lang="EN-US">&nbsp;</span></p>
<p class="MsoNormal"><span lang="EN-US">CTS</span><span style="FONT-FAMILY: 宋体">和</span><span lang="EN-US">C#</span><span style="FONT-FAMILY: 宋体">一个重要的作用是提供一种专用类型表示财务计算，这就是</span><span lang="EN-US">decimal</span><span style="FONT-FAMILY: 宋体">类型，使用</span><span lang="EN-US">decimal</span><span style="FONT-FAMILY: 宋体">类型提供的</span><span lang="EN-US">28</span><span style="FONT-FAMILY: 宋体">位的方式取决于用户。换言之，可以用较大的精确度</span><span lang="EN-US">(</span><span style="FONT-FAMILY: 宋体">带有美分</span><span lang="EN-US">)</span><span style="FONT-FAMILY: 宋体">来表示较小的美元值，也可以在小数部分用更多的舍入来表示较大的美元值。但应注意，</span><span lang="EN-US">decimal</span><span style="FONT-FAMILY: 宋体">类型不是基本类型，所以在计算时使用该类型会有性能损失。</span></p>
<p class="MsoNormal"><span style="FONT-FAMILY: 宋体">要把数字指定为</span><span lang="EN-US">decimal</span><span style="FONT-FAMILY: 宋体">类型，而不是</span><span lang="EN-US">double</span><span style="FONT-FAMILY: 宋体">、</span><span lang="EN-US"> float</span><span style="FONT-FAMILY: 宋体">或整型，可以在数字的后面加上字符</span><span lang="EN-US">M(</span><span style="FONT-FAMILY: 宋体">或</span><span lang="EN-US">m)</span><span style="FONT-FAMILY: 宋体">，如下所示。</span></p>
<p class="2" style="MARGIN: 8.15pt 0cm 8.15pt 21.45pt; TEXT-INDENT: 18.45pt"><span lang="EN-GB">decimal d = 12.30M;</span></p>
<h4 style="TEXT-INDENT: 21.45pt"><span lang="EN-GB">4. bool</span><span style="FONT-FAMILY: 黑体">类型</span></h4>
<p class="MsoNormal"><span lang="EN-US">C#</span><span style="FONT-FAMILY: 宋体">的</span> <span></span><span lang="EN-US">bool </span><span style="FONT-FAMILY: 宋体">类型用于包含</span><span lang="EN-US">bool</span><span style="FONT-FAMILY: 宋体">值</span><span lang="EN-US">true</span><span style="FONT-FAMILY: 宋体">或</span><span lang="EN-US">false</span><span style="FONT-FAMILY: 宋体">，</span><span style="FONT-FAMILY: 宋体">如表</span><span lang="EN-US">2-4</span><span style="FONT-FAMILY: 宋体">所示。</span></p>
<p class="a5" style="MARGIN-TOP: 8.15pt"><span style="FONT-FAMILY: 黑体">表</span><span lang="EN-US">&nbsp; 2-4</span></p>
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            <p class="a2" style="LINE-HEIGHT: 14pt"><span style="FONT-FAMILY: 黑体">名</span><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'">&nbsp;&nbsp; &nbsp;&nbsp;</span><span style="FONT-FAMILY: 黑体">称</span></p>
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            <p class="a2" style="LINE-HEIGHT: 14pt"><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'">CTS&nbsp; </span><span style="FONT-FAMILY: 黑体">类</span><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'">&nbsp; </span><span style="FONT-FAMILY: 黑体">型</span></p>
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            <td style="BORDER-RIGHT: medium none; PADDING-RIGHT: 9.9pt; BORDER-TOP: windowtext 1pt solid; PADDING-LEFT: 9.9pt; PADDING-BOTTOM: 1.4pt; BORDER-LEFT: medium none; WIDTH: 195.9pt; PADDING-TOP: 1.4pt; BORDER-BOTTOM: windowtext 1pt solid" valign="top" width="261">
            <p class="a2" style="TEXT-JUSTIFY: inter-ideograph; TEXT-INDENT: 83.6pt; LINE-HEIGHT: 14pt; TEXT-ALIGN: justify"><span style="FONT-FAMILY: 黑体">值</span></p>
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            <p class="a4" style="MARGIN-LEFT: 0cm; LINE-HEIGHT: 14pt; TEXT-ALIGN: center" align="center"><span lang="EN-US">bool</span></p>
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            <p class="a4" style="MARGIN-LEFT: 0cm; LINE-HEIGHT: 14pt; TEXT-ALIGN: center" align="center"><span lang="EN-US">System.Boolean</span></p>
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            <p class="a4" style="MARGIN-LEFT: 0cm; LINE-HEIGHT: 14pt; TEXT-ALIGN: center" align="center"><span lang="EN-US">true</span><span style="FONT-FAMILY: 宋体">或</span><span lang="EN-US">false</span></p>
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<p class="MsoNormal"><span lang="EN-US">&nbsp;</span></p>
<p class="MsoNormal"><span lang="EN-US">bool</span><span style="FONT-FAMILY: 宋体">值和整数值不能相互转换。如果变量</span><span lang="EN-US">(</span><span style="FONT-FAMILY: 宋体">或函数的返回类型</span><span lang="EN-US">)</span><span style="FONT-FAMILY: 宋体">声明为</span><span lang="EN-US">bool</span><span style="FONT-FAMILY: 宋体">类型，就只能使用值</span><span lang="EN-US">true</span><span style="FONT-FAMILY: 宋体">或</span><span lang="EN-US">false</span><span style="FONT-FAMILY: 宋体">。如果试图使用</span><span lang="EN-US">0</span><span style="FONT-FAMILY: 宋体">表示</span><span lang="EN-US">false</span><span style="FONT-FAMILY: 宋体">，非</span><span lang="EN-US">0</span><span style="FONT-FAMILY: 宋体">值表示</span><span lang="EN-US">true</span><span style="FONT-FAMILY: 宋体">，就会出错。</span></p>
<h4 style="TEXT-INDENT: 21.45pt"><span lang="EN-GB">5. </span><span style="FONT-FAMILY: 黑体">字符类型</span></h4>
<p class="MsoNormal"><span></span><span><span style="FONT-FAMILY: 宋体">为了保存单个字符的值</span></span><span style="FONT-FAMILY: 宋体">，</span><span lang="EN-US">C#</span><span style="FONT-FAMILY: 宋体">支持</span><span lang="EN-US">char</span><span style="FONT-FAMILY: 宋体">数据类型</span><span style="FONT-FAMILY: 宋体">，</span><span style="FONT-FAMILY: 宋体">如表</span><span lang="EN-US">2-5</span><span style="FONT-FAMILY: 宋体">所示。</span></p>
<p class="a5" style="MARGIN-TOP: 8.15pt"><span style="FONT-FAMILY: 黑体">表</span><span lang="EN-US">&nbsp; 2-5</span></p>
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            <p class="a2" style="LINE-HEIGHT: 14pt"><span style="FONT-FAMILY: 黑体">名</span><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'">&nbsp; &nbsp;&nbsp;</span><span style="FONT-FAMILY: 黑体">称</span></p>
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            <td style="BORDER-RIGHT: windowtext 1pt solid; PADDING-RIGHT: 9.9pt; BORDER-TOP: windowtext 1pt solid; PADDING-LEFT: 9.9pt; PADDING-BOTTOM: 1.4pt; BORDER-LEFT: medium none; WIDTH: 117.7pt; PADDING-TOP: 1.4pt; BORDER-BOTTOM: windowtext 1pt solid" valign="top" width="157">
            <p class="a2" style="LINE-HEIGHT: 14pt"><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'">CTS&nbsp; </span><span style="FONT-FAMILY: 黑体">类</span><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'">&nbsp; </span><span style="FONT-FAMILY: 黑体">型</span></p>
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            <td style="BORDER-RIGHT: medium none; PADDING-RIGHT: 9.9pt; BORDER-TOP: windowtext 1pt solid; PADDING-LEFT: 9.9pt; PADDING-BOTTOM: 1.4pt; BORDER-LEFT: medium none; WIDTH: 195.95pt; PADDING-TOP: 1.4pt; BORDER-BOTTOM: windowtext 1pt solid" valign="top" width="261">
            <p class="a2" style="LINE-HEIGHT: 14pt"><span style="FONT-FAMILY: 黑体">值</span></p>
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            <td style="BORDER-RIGHT: windowtext 1pt solid; PADDING-RIGHT: 9.9pt; BORDER-TOP: medium none; PADDING-LEFT: 9.9pt; PADDING-BOTTOM: 1.4pt; BO