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<p class="2" style="MARGIN-LEFT: 21.45pt; FTEL: 18.45pt"><span lang="EN-US">{</span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; FTEL: 18.45pt"><span lang="EN-US">&nbsp;&nbsp; //Fill the data adapter from the database</span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; FTEL: 32.25pt"><span lang="EN-US">supplierDataAdapter1.Fill (supplierDataSet , &quot;Supplier&quot;) ;</span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; FTEL: 32.25pt"><span lang="EN-US">&nbsp;</span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; FTEL: 32.25pt"><span lang="EN-US">//And display the data in the data grid&hellip;</span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; FTEL: 18.45pt"><span lang="EN-US">&nbsp;&nbsp; dataGrid1.SetDataBinding (supplierDataSet , &quot;Supplier&quot;) ;</span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; FTEL: 18.45pt"><span lang="EN-US">&nbsp;</span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; FTEL: 32.25pt"><span lang="EN-US">//And disable the retrieve button&hellip;</span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; FTEL: 32.25pt"><span lang="EN-US">retrieveButton.Enabled = fasle;</span></p>
<p class="2" style="MARGIN-TOP: 0cm; MARGIN-LEFT: 21.45pt; MARGIN-RIGHT: 0cm; FTEL: 18.45pt"><span lang="EN-US">}</span></p>
<p class="MsoNormal"><span style="FONT-FAMILY: 宋体">这段代码利用前面创建的</span><span lang="EN-US">DataAdapter(</span><span style="FONT-FAMILY: 宋体">从</span><span lang="EN-US">Server Explorer</span><span style="FONT-FAMILY: 宋体">拖放一个数据库表</span><span lang="EN-US">)</span><span style="FONT-FAMILY: 宋体">填充</span><span class="codeintext-PRODUCTION"><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'">DataSet</span></span><span class="codeintext-PRODUCTION"><span style="FONT-FAMILY: 宋体">。我们填充了</span></span><span lang="EN-US">Supplier</span><span class="codeintext-PRODUCTION"><span style="FONT-FAMILY: 宋体">数据表和数据库中的所有记录。接着调用</span></span><span class="codeintext-PRODUCTION"><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'">SetDataBinding()</span></span><span class="codeintext-PRODUCTION"><span style="FONT-FAMILY: 宋体">，在屏幕上显示这些记录。</span></span></p>
<p class="MsoNormal"><span class="codeintext-PRODUCTION"><span style="FONT-FAMILY: 宋体">在浏览了数据，进行了一些修改后，就可以单击</span></span><span class="screentext-PRODUCTION"><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'; LETTER-SPACING: 0pt">Update</span></span><span class="screentext-PRODUCTION"><span style="FONT-FAMILY: 宋体; LETTER-SPACING: 0pt">按钮，执行如下代码：</span></span></p>
<p class="2" style="MARGIN-TOP: 8.15pt; MARGIN-LEFT: 21.45pt; MARGIN-RIGHT: 0cm; FTEL: 18.45pt"><span lang="EN-US">private void updateButton_Click(object sender, System.EventArgs e)</span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; FTEL: 18.45pt"><span lang="EN-US">{</span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; FTEL: 18.45pt"><span lang="EN-US">&nbsp;&nbsp; //Update the database</span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; FTEL: 18.45pt"><span lang="EN-US">&nbsp;&nbsp; int modified = supplierDataAdapter.Update(supplierDataSet, &quot; Supplier&quot; ) ;</span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; FTEL: 18.45pt"><span lang="EN-US">&nbsp; </span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; FTEL: 18.45pt"><span lang="EN-US">&nbsp;&nbsp; if (modified &gt; 0)</span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; FTEL: 18.45pt"><span lang="EN-US">&nbsp;&nbsp;&nbsp;&nbsp; MessageBox.Show9 string.Format (&quot;Modified {o} rows&quot; , modified));</span></p>
<p class="2" style="MARGIN-TOP: 0cm; MARGIN-LEFT: 21.45pt; MARGIN-RIGHT: 5.35pt; FTEL: 18.45pt"><span lang="EN-US">}</span></p>
<p class="MsoNormal"><span style="FONT-FAMILY: 宋体">这段代码也是很简单的，因为</span><span lang="EN-US">DataAdapter</span><span style="FONT-FAMILY: 宋体">完成了大部分工作。</span><span class="codeintext-PRODUCTION"><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'">Update()</span></span><span class="codeintext-PRODUCTION"><span style="FONT-FAMILY: 宋体">方法迭代</span></span><span class="codeintext-PRODUCTION"><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'">DataSet</span></span><span class="codeintext-PRODUCTION"><span style="FONT-FAMILY: 宋体">被选中的表中的数据，在数据库上对每个修改执行相应的</span></span><span class="codeintext-PRODUCTION"><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'">SQL</span></span><span class="codeintext-PRODUCTION"><span style="FONT-FAMILY: 宋体">语句，注意这个方法返回一个</span></span><span class="codeintext-PRODUCTION"><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'">int</span></span><span class="codeintext-PRODUCTION"><span style="FONT-FAMILY: 宋体">型的值，这是</span></span><span class="codeintext-PRODUCTION"><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'">Updata()</span></span><span class="codeintext-PRODUCTION"><span style="FONT-FAMILY: 宋体">方法所修改的行数。这个示例利用这个数字显示被修改的行数。</span></span></p>
<p class="MsoNormal"><span class="codeintext-PRODUCTION"><span style="FONT-FAMILY: 宋体">第</span></span><span class="codeintext-PRODUCTION"><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'">21</span></span><span class="codeintext-PRODUCTION"><span style="FONT-FAMILY: 宋体">章详细讨论了</span></span><span lang="EN-US">DataAdapter</span><span style="FONT-FAMILY: 宋体">的使用，简言之，它代表了</span><span class="codeintext-PRODUCTION"><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'">SELECT</span></span><span class="codeintext-PRODUCTION"><span style="FONT-FAMILY: 宋体">、</span></span><span class="codeintext-PRODUCTION"><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'">INSERT</span></span><span class="codeintext-PRODUCTION"><span style="FONT-FAMILY: 宋体">、</span></span><span class="codeintext-PRODUCTION"><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'">UPDATE</span></span><span class="codeintext-PRODUCTION"><span style="FONT-FAMILY: 宋体">和</span></span><span class="codeintext-PRODUCTION"><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'">DELETE</span></span><span class="codeintext-PRODUCTION"><span style="FONT-FAMILY: 宋体">操作的</span></span><span class="codeintext-PRODUCTION"><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'">SQL</span></span><span class="codeintext-PRODUCTION"><span style="FONT-FAMILY: 宋体">语句。当调用</span></span><span class="codeintext-PRODUCTION"><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'">Update()</span></span><span class="codeintext-PRODUCTION"><span style="FONT-FAMILY: 宋体">方法时，它对每个已修改的行执行相应的语句，这会使所有已修改的行执行</span></span><span class="codeintext-PRODUCTION"><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'">UPDATE</span></span><span class="codeintext-PRODUCTION"><span style="FONT-FAMILY: 宋体">语句，所有已删除的行执行</span></span><span class="codeintext-PRODUCTION"><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'">DELETE</span></span><span class="codeintext-PRODUCTION"><span style="FONT-FAMILY: 宋体">语句等。所执行的命令在默认情况下都是简单的</span></span><span class="codeintext-PRODUCTION"><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'">SQL</span></span><span class="codeintext-PRODUCTION"><span style="FONT-FAMILY: 宋体">语句。还可以创建相应的命令对象，把它们赋予</span></span><span lang="EN-US">DataAdapter</span><span style="FONT-FAMILY: 宋体">的属性，从而使用存储过程。</span></p>
<p class="MsoNormal"><span class="codeintext-PRODUCTION"><span style="FONT-FAMILY: 宋体">如果要利用存储过程的所有优点，但没有时间编写自己的存储过程，可以使用</span></span><span lang="EN-US">Visual Studio .NET</span><span style="FONT-FAMILY: 宋体">向导。从</span><span lang="EN-US">DataAdapter</span><span style="FONT-FAMILY: 宋体">的关联菜单中，选择</span><span class="screentext-PRODUCTION"><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'">Configure Data Adapter</span></span><span class="screentext-PRODUCTION"><span style="FONT-FAMILY: 宋体">菜单项，就会显示一个</span></span><span class="screentext-PRODUCTION"><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'">Configuration</span></span><span class="screentext-PRODUCTION"><span style="FONT-FAMILY: 宋体">向导，在其中选择</span></span><span lang="EN-US">DataAdapter</span><span style="FONT-FAMILY: 宋体">的数据源，如图</span><span lang="EN-US">22-24</span><span style="FONT-FAMILY: 宋体">所示。</span></p>
<p class="MsoNormal"><a ftel="Wizard1"><span style="FONT-FAMILY: 宋体">在选择</span><span class="screentext-PRODUCTION"><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'; LETTER-SPACING: 0pt">Create new stored procedures</span></span></a><span class="screentext-PRODUCTION"><span style="FONT-FAMILY: 宋体; LETTER-SPACING: 0pt">后，单击</span></span><span class="screentext-PRODUCTION"><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'; LETTER-SPACING: 0pt">Next</span></span><span class="screentext-PRODUCTION"><span style="FONT-FAMILY: 宋体; LETTER-SPACING: 0pt">，就进入自动为</span></span><span class="codeintext-PRODUCTION"><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'">SELECT</span></span><span class="codeintext-PRODUCTION"><span style="FONT-FAMILY: 宋体">、</span></span><span class="codeintext-PRODUCTION"><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'">INSERT</span></span><span class="codeintext-PRODUCTION"><span style="FONT-FAMILY: 宋体">、</span></span><span class="codeintext-PRODUCTION"><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'">UPDATE</span></span><span style="FONT-FAMILY: 宋体">和</span><span class="codeintext-PRODUCTION"><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'">DELETE</span></span><span class="codeintext-PRODUCTION"><span style="FONT-FAMILY: 宋体">语句生成新存储过程的向导页面，最后修改项目中生成的代码，添加对这些存储过程的调用，而不是直接调用</span></span><span class="codeintext-PRODUCTION"><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'">SQL</span></span><span class="codeintext-PRODUCTION"><span style="FONT-FAMILY: 宋体">语句。</span></span></p>
<p class="MsoNormal"><span style="FONT-FAMILY: 宋体">除了生成新的存储过程外，还可以选择现有的存储过程，填充</span><span lang="EN-US">DataAdapter</span><span style="FONT-FAMILY: 宋体">上的</span><span lang="EN-US">4</span><span style="FONT-FAMILY: 宋体">个</span><span lang="EN-US">SQL</span><span style="FONT-FAMILY: 宋体">命令。当手工编写的存储过程已经可以使用时，或者存储过程执行其他一些函数</span><span lang="EN-US">(</span><span style="FONT-FAMILY: 宋体">例如审查改变或更新链接的记录等</span><span lang="EN-US">)</span><span style="FONT-FAMILY: 宋体">时，这种方式是很有效的。</span></p>
<p align="center"><span lang="EN-US"><img height="306" src="22/image024.jpg" width="340" alt="" /></span></p>
<p style="FTEL: 8.15pt" align="center"><span style="FONT-FAMILY: 宋体">图</span><span lang="EN-US">&nbsp; 22-24</span></p></div>
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                        <h1 id="divCurrentNode2" style="color: #b83507; width: 100%; text-align: left; font-size: 12px; padding-left: 2px">当前章节:<a href='100165631.htm'><font color='red'>22.3.4  更新数据源</font></a></h1>
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                        <div style='float:left;width:49%'>·<a href='100165628.htm'>22.3.1  创建一个连接</a></div><div style='float:right;width:49%'>·<a href='100165629.htm'>22.3.2  选择数据</a></div><div style='float:left;width:49%'>·<a href='100165630.htm'>22.3.3  生成DataSet</a></div><div style='float:right;width:49%'>·<a href='100165632.htm'>22.3.5  构建模式</a></div><div style='float:left;width:49%'>·<a href='100165633.htm'>22.3.6  其他常见的要求</a></div><div style='float:right;width:49%'>·<a href='100165634.htm'>22.4  小结</a></div></div>
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