通过DataSet更新、插入数据库

方法一：
//与SQL Server的连接字符串设置
private string _connString;
private string _strSql;
private SqlCommandBuilder sqlCmdBuilder;
private DataSet ds = new DataSet();
private SqlDataAdapter da;
public sqlAccess(string connString,string strSql)
{
this._connString=connString;
}
private SqlConnection GetConn()
{
try
{
SqlConnection Connection = new SqlConnection(this._connString);
Connection.Open();
return Connection;
}
catch (Exception ex)
{
MessageBox.Show(ex.Message,"数据库连接失败");
throw;
}
}
//根据输入的SQL语句检索数据库数据
public DataSet SelectDb(string strSql,string strTableName)
{
try
{
this._strSql = strSql;
this.da = new SqlDataAdapter(this._strSql,this.GetConn());
this.ds.Clear();
this.da.Fill(ds,strTableName);
return ds;//返回填充了数据的DataSet，其中数据表以strTableName给出的字符串命名
}
catch (Exception ex)
{
MessageBox.Show(ex.Message,"数据库操作失败");
throw;
}
}
//数据库数据更新(传DataSet和DataTable的对象)
public DataSet UpdateDs(DataSet changedDs,string tableName)
{
try
{
this.da = new SqlDataAdapter(this._strSql,this.GetConn());
this.sqlCmdBuilder = new SqlCommandBuilder(da);
this.da.Update(changedDs,tableName);
changedDs.AcceptChanges();
return changedDs;//返回更新了的数据库表
}
catch (Exception ex)
{
MessageBox.Show(ex.Message,"数据库更新失败");
throw;
}
}

1. GetConn方法创建一个数据库连接，返回SqlConnection。
2.使用的select命令中必须包含主键，这点大家都知道的!
3. this.da.Fill(ds,strTableName) 填充数据集
4.构造CommandBuilder对象时,将DataAdapter对象作为构造函数参数传入:
this.sqlCmdBuilder = new SqlCommandBuilder(da);
5. 在调用UpdateDs()更新数据库前，请检查changedDs是否已经被更新过，用changedDs.[tableName] GetChanges() != null;
6.用this.da.Update(changedDs,tableName)方法更新数据,然后调用changedDs.AcceptChanges()才能真正的更新数据库，调用 changedDs.RejectChanges() 取消更新。

方法二：
该方法可能存在性能问题
int tab1Count = ds.Tables["ruledetail_setup"].Rows.Count;
for (int i = 0; i < tab1Count; i++)
{
string sql = "select count(*) from ruledetail_setup where type = " + type + " and ID = ";
sql += ds.Tables["ruledetail_setup"].Rows[i]["ID"];
if (Convert.ToInt32(SqlHelper.ExecuteScalar(CommandType.Text, sql, null)) != 0)
{
string sqlUpdata = "updata ruledetail_setup set errorLimit={0},scoreInterval={1},detailRule={2},gradeTime={3} ";
sqlUpdata += "where type = " + type + " and ID = " + ds.Tables["ruledetail_setup"].Rows[i]["ID"];
String.Format(sqlUpdata,
ds.Tables["ruledetail_setup"].Rows[i]["errorLimit"],
ds.Tables["ruledetail_setup"].Rows[i]["scoreInterval"],
ds.Tables["ruledetail_setup"].Rows[i]["detailRule"],
ds.Tables["ruledetail_setup"].Rows[i]["gradeTime"]);
SqlHelper.ExecuteNonQuery(CommandType.Text, sqlUpdata, null);
}
else
{
string sqlIns = "insert into ruledetail_setup (Type,ID,errorLimit,scoreInterval,detailRule,gradeTime) ";
sqlIns += "values ("+type+",{0},{1},{2},{3},{4})";
String.Format(sqlIns,
ds.Tables["ruledetail_setup"].Rows[i]["ID"],
ds.Tables["ruledetail_setup"].Rows[i]["errorLimit"],
ds.Tables["ruledetail_setup"].Rows[i]["scoreInterval"],
ds.Tables["ruledetail_setup"].Rows[i]["detailRule"],
ds.Tables["ruledetail_setup"].Rows[i]["gradeTime"]);
SqlHelper.ExecuteNonQuery(CommandType.Text, sqlIns, null);
}
}