开发时数据调用往往会用到占位符，然而刚开始使用很容易碰见sql语句在SQLServer中查询时显示“—”，如下代码：

	#region 先判断是否有记录，再确定使用哪条命令

			//查询数据库  20140713
            commandText = "use zzbjcdzz select *"
                                 + "from [T_VillageBasicInfo] "
								 + "where ltrim(rtrim([code]))='{0}' ";

			//注意参数
			commandText = String.Format(commandText, root.SelectSingleNode("region").InnerText);

			//执行查询
			dataTable = dataEngine.Select(commandText, out execRight, out retMsg);

			//如果存在，则使用update
            //20140714  有错误================================
			if (dataTable.Rows.Count > 0)
			{

				//查询数据库
                commandText = "use zzbjcdzz  update [T_VillageBasicInfo] "
                  + " set [population]={0},[area]={1},[Describes]='{2}',[Date]='{3}',[LeadingIndustry]='{4}',[AnnualIncome]={5},[Award]='{6}',[TeamSubsidy]={7},[PartyBuildTotalNum]={8}"
				   + "where ltrim(rtrim([Code]))='{9}'";
             
				//注意
				commandText = String.Format(commandText, root.SelectSingleNode("population").InnerText,
                                 root.SelectSingleNode("area").InnerText,root.SelectSingleNode("Describes").InnerText,root.SelectSingleNode("Date").InnerText,
                                 root.SelectSingleNode("LeadingIndustry").InnerText,root.SelectSingleNode("AnnualIncome").InnerText,root.SelectSingleNode("Award").InnerText,
                                 root.SelectSingleNode("TeamSubsidy").InnerText,root.SelectSingleNode("PartyBuildTotalNum").InnerText,root.SelectSingleNode("region").InnerText);
			}
			else
			{

				//查询数据库
                commandText = "insert into [T_VillageBasicInfo]([population],[area],[code],[Describes],[Date],[LeadingIndustry],[AnnualIncome],[Award],[TeamSubsidy],[PartyBuildTotalNum]) values({0},{1},'{2}',{3},'{4}','{5}','{6}',{7},'{8}',{9},{10} ";

				//注意
				commandText = String.Format(commandText, root.SelectSingleNode("population").InnerText,
								root.SelectSingleNode("area").InnerText, root.SelectSingleNode("region").InnerText,root.SelectSingleNode("Describes").InnerText, root.SelectSingleNode("Date").InnerText, 
                                 root.SelectSingleNode("LeadingIndustry").InnerText, root.SelectSingleNode("AnnualIncome").InnerText, root.SelectSingleNode("Award").InnerText,
                                 root.SelectSingleNode("TeamSubsidy").InnerText, root.SelectSingleNode("PartyBuildTotalNum").InnerText);
			}
			//执行查询
			dataEngine.Execute(commandText, out execRight, out retMsg);

			if (execRight == true)
			{ result = "<root><success>true</success><message>更新成功</message></root>"; }
			else
			{ result = "<root><success>false</success><message>更新失败</message></root>"; }

<pre name="code" class="csharp">set [population]={0},[area]={1},[Describes]='{2}',[Date]='{3}',[LeadingIndustry]='{4}',[AnnualIncome]={5},[Award]='{6}',[TeamSubsidy]={7},[PartyBuildTotalNum]={8}

（给出代码供大家参考这种替换方式）

开发问题---数据库字段前出现“—”（保存留用，仅供参考）,布布扣,bubuko.com

开发问题---数据库字段前出现“—”（保存留用，仅供参考）