C# 用DataSet.ReadXMl()读取数据后,更新数据库。怎么实现
<?xml version="1.0" encoding="utf-8" ?>
<Pre>
<test>
<c>301</c>
<c1>1001</c1>
<c2>222</c2>
</test>
<test>
<c>302</c>
<c1>61</c1>
<c2>2002</c2>
</test>
<test>
<c>303</c>
<c1>71</c1>
<c2>3003</c2>
</test>
</Pre>
上面是XML格式的数据
CREATE TABLE [dbo].[t_Test](
[iSeq] [int] IDENTITY(1,1) NOT NULL,
[cID] [nchar](10) NULL,
[cXM] [nchar](10) NULL,
CONSTRAINT [PK_t_Test] PRIMARY KEY CLUSTERED
(
[iSeq] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]
上面是表结构
SqlConnection myConn = new SqlConnection("Server=.;database=SCM_CTM_Test;UID=;PWD=;Connect Timeout=300;");
DataSet ds = new DataSet();//更新的表必须有一个主键,iSeq就是主键
ds.ReadXml(Application.StartupPath + "\\Test.xml");
ds.Tables[0].TableName = "t_Ds";
SqlDataAdapter myDa = new SqlDataAdapter("select iSeq as c,cID as c1,cXM as c2 from t_Test", myConn);
SqlCommandBuilder myBu = new SqlCommandBuilder(myDa);
myDa.Update(ds, "t_Ds");
ds.AcceptChanges();
这段代码,为什么不能实现更新t_Test表中iSeq = 301,302,303的数据,而是插入3条新的数据呢?
求解答!!!!!!