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<p class="MsoNormal"><span style="FONT-FAMILY: 宋体">生成的</span><span lang="EN-US"> ProductRow </span><span style="FONT-FAMILY: 宋体">类如下所示：</span></p>
<p class="2" style="MARGIN-TOP: 8.15pt; MARGIN-LEFT: 21.45pt; MARGIN-RIGHT: 0cm; FTEL: 18.45pt"><span lang="EN-US">public class ProductRow : DataRow</span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; LINE-HEIGHT: 15pt; FTEL: 18.45pt"><span lang="EN-US">{</span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; LINE-HEIGHT: 15pt; FTEL: 18.45pt"><span lang="EN-US">&nbsp;&nbsp; private ProductDataTable tableProduct;</span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; LINE-HEIGHT: 15pt; FTEL: 18.45pt"><span lang="EN-US">&nbsp;&nbsp; internal ProductRow(DataRowBuilder rb) : base(rb)</span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; LINE-HEIGHT: 15pt; FTEL: 18.45pt"><span lang="EN-US">&nbsp; {</span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; LINE-HEIGHT: 15pt; FTEL: 18.45pt"><span lang="EN-US">&nbsp;&nbsp;&nbsp; this.tableProduct = ((ProductDataTable)(this.Table));</span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; LINE-HEIGHT: 15pt; FTEL: 18.45pt"><span lang="EN-US">&nbsp; }</span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; LINE-HEIGHT: 15pt; FTEL: 18.45pt"><span lang="EN-US">&nbsp;&nbsp; public string Name { ... }</span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; LINE-HEIGHT: 15pt; FTEL: 18.45pt"><span lang="EN-US">&nbsp;&nbsp; public bool IsNameNull { ... }</span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; LINE-HEIGHT: 15pt; FTEL: 18.45pt"><span lang="EN-US">&nbsp;&nbsp; public void SetNameNull { ... }</span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; LINE-HEIGHT: 15pt; FTEL: 18.45pt"><span lang="EN-US">&nbsp; // Other accessors/mutators omitted for clarity</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" style="LINE-HEIGHT: 17pt"><span style="FONT-FAMILY: 宋体">把属性添加到元素上时，就会把一个特性添加到生成的</span><span lang="EN-US">DataRow</span><span style="FONT-FAMILY: 宋体">类上，如上述代码所示。该特性与属性有相同的名称，所以在上面的示例中，</span><span lang="EN-US">Product</span><span style="FONT-FAMILY: 宋体">行包含</span><span class="codeintext-PRODUCTION"><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'">Name</span></span><span style="FONT-FAMILY: 宋体">、</span><span class="codeintext-PRODUCTION"><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'">SKU</span></span><span style="FONT-FAMILY: 宋体">、</span><span class="codeintext-PRODUCTION"><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'">Description</span></span><span class="codeintext-PRODUCTION"><span style="FONT-FAMILY: 宋体; LETTER-SPACING: 0.2pt">和</span></span><span class="codeintext-PRODUCTION"><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'">Price</span></span><span class="codeintext-PRODUCTION"><span style="FONT-FAMILY: 宋体">特性。</span></span></p>
<p class="MsoNormal" style="LINE-HEIGHT: 17pt"><span style="FONT-FAMILY: 宋体">对于每个新添加的属性，都对</span><span lang="EN-US">.cs</span><span style="FONT-FAMILY: 宋体">文件进行了几处修改。在下面的示例中，假定添加了一个类型为</span><span lang="EN-US">int</span><span style="FONT-FAMILY: 宋体">的属性</span><span lang="EN-US">ProductId</span><span style="FONT-FAMILY: 宋体">。</span></p>
<p class="MsoNormal" style="LINE-HEIGHT: 17pt"><span style="FONT-FAMILY: 宋体">首先给</span><span lang="EN-US">ProductDataTable</span><span style="FONT-FAMILY: 宋体">类</span><span lang="EN-US">(</span><span style="FONT-FAMILY: 宋体">派生于</span><span lang="EN-US">DataTable)</span><span style="FONT-FAMILY: 宋体">添加一个私有成员，即新的</span><span lang="EN-US">DataColumn</span><span style="FONT-FAMILY: 宋体">：</span></p>
<p class="2" style="MARGIN-TOP: 9.8pt; MARGIN-LEFT: 21.45pt; MARGIN-RIGHT: 0cm; FTEL: 18.45pt"><span lang="EN-US">private DataColumn columnProductId;</span></p>
<p class="MsoNormal"><span style="FONT-FAMILY: 宋体">用属性</span><span lang="EN-US">ProductIDColumn</span><span style="FONT-FAMILY: 宋体">来连接，这个属性被定义为</span><span lang="EN-US">internal</span><span style="FONT-FAMILY: 宋体">：</span></p>
<p class="2" style="MARGIN-TOP: 9.8pt; MARGIN-LEFT: 21.45pt; MARGIN-RIGHT: 0cm; FTEL: 18.45pt"><span lang="EN-US">internal DataColumn ProductIdColumn</span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; LINE-HEIGHT: 15pt; FTEL: 18.45pt"><span lang="EN-US">{</span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; LINE-HEIGHT: 15pt; FTEL: 18.45pt"><span lang="EN-US">&nbsp;&nbsp; get { return this.columnProductId; }</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" style="LINE-HEIGHT: 17pt"><span style="FONT-FAMILY: 宋体">上面的</span><span lang="EN-US">AddProductRow()</span><span style="FONT-FAMILY: 宋体">方法也做了修改，该函数现在带有一个整型参数</span><span lang="EN-US">ProductID</span><span style="FONT-FAMILY: 宋体">，并存储了在新建列中输入的值：</span></p>
<p class="2" style="MARGIN-TOP: 9.8pt; MARGIN-LEFT: 21.45pt; MARGIN-RIGHT: 0cm; FTEL: 18.45pt"><span lang="EN-US">public ProductRow AddProductRow ( ... , int ProductId)</span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; LINE-HEIGHT: 15pt; FTEL: 18.45pt"><span lang="EN-US">{</span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; LINE-HEIGHT: 15pt; FTEL: 18.45pt"><span lang="EN-US">&nbsp;&nbsp; ProductRow rowProductRow = ((ProductRow)(this.NewRow()));</span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; LINE-HEIGHT: 15pt; FTEL: 18.45pt"><span lang="EN-US">&nbsp;&nbsp; rowProductRow.ItemArray = new Object[] { ... , ProductId};</span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; LINE-HEIGHT: 15pt; FTEL: 18.45pt"><span lang="EN-US">&nbsp;&nbsp; this.Rows.Add(rowProductRow);</span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; LINE-HEIGHT: 15pt; FTEL: 18.45pt"><span lang="EN-US">&nbsp;&nbsp; return rowProductRow;</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">最后在</span><span lang="EN-US">ProductDataTable</span><span style="FONT-FAMILY: 宋体">中修改</span><span lang="EN-US">InitClass()</span><span style="FONT-FAMILY: 宋体">方法：</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 InitClass()</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; ...</span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; FTEL: 18.45pt"><span lang="EN-US">&nbsp; this.columnProductID = new DataColumn(&quot;ProductID&quot;, typeof(int), null, </span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; FTEL: 18.45pt"><span lang="EN-US">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; System.Data.MappingType.Attribute);</span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; FTEL: 18.45pt"><span lang="EN-US">&nbsp; this.Columns.Add(this.columnProductID);</span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; FTEL: 18.45pt"><span lang="EN-US">&nbsp; this.columnProductID.Namespace = &quot;&quot;;</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">这段代码创建了新的</span><span lang="EN-US">DataColumn</span><span style="FONT-FAMILY: 宋体">，并把它添加到</span><span lang="EN-US">DataTable</span><span style="FONT-FAMILY: 宋体">的</span><span lang="EN-US">Columns</span><span style="FONT-FAMILY: 宋体">集合中。</span><span lang="EN-US">DataColumn</span><span style="FONT-FAMILY: 宋体">构造函数的最后一个参数定义了在把</span><span lang="EN-US">DataSet</span><span style="FONT-FAMILY: 宋体">保存到</span><span lang="EN-US">XML</span><span style="FONT-FAMILY: 宋体">文件中时，该列如何映射回</span><span lang="EN-US">XML</span><span style="FONT-FAMILY: 宋体">上。</span></p>
<p class="MsoNormal"><span style="FONT-FAMILY: 宋体">更新</span><span lang="EN-US">ProductRow</span><span style="FONT-FAMILY: 宋体">类，并给这个列添加一个访问器：</span></p>
<p class="2" style="MARGIN-TOP: 8.15pt; MARGIN-LEFT: 21.45pt; MARGIN-RIGHT: 0cm; FTEL: 18.45pt"><span lang="EN-US">public int ProductId</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; get { return ((int)(this[this.tableProduct.ProductIdColumn])); }</span></p>
<p class="2" style="MARGIN-LEFT: 21.45pt; FTEL: 18.45pt"><span lang="EN-US">&nbsp;&nbsp; set { this[this.tableProduct.ProductIdColumn] = value; }</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>
<h4 style="FTEL: 21.45pt"><span lang="EN-US">4. </span><span style="FONT-FAMILY: 黑体">生成的</span><span lang="EN-US">EventArgs</span></h4>
<p class="MsoNormal"><span style="FONT-FAMILY: 宋体">最后一个添加到源代码中的类是</span><span lang="EN-US">EventArgs</span><span style="FONT-FAMILY: 宋体">的一个派生类，它提供的方法可以直接访问已经改变</span><span lang="EN-US">(</span><span style="FONT-FAMILY: 宋体">或者正在改变</span><span lang="EN-US">)</span><span style="FONT-FAMILY: 宋体">的行，以及应用到该行上的操作。这里为了简洁起见，省略了这段代码。</span></p></div>
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