select * from table where 物品编号=A
把这个sql语句传给类似下面的过程去执行,如果得到null,则说明不存在,如果不是null,
则说明已经有该物品了。
public DataRow showDataRow(string Sql)
{
DataRow myDatarow;
DataSet dataSet1 = new DataSet();
SqlDataAdapter dataAdapter1;
SqlConnection conn1 = new SqlConnection(DSN);
dataAdapter1= new SqlDataAdapter(Sql,conn1);
dataAdapter1.Fill(dataSet1,"table1"); try
{
myDatarow = dataSet1.Tables["table1"].Rows[0];
}
catch
{
myDatarow = null;
}
return myDatarow;
}
把这个sql语句传给类似下面的过程去执行,如果得到null,则说明不存在,如果不是null,
则说明已经有该物品了。
public DataRow showDataRow(string Sql)
{
DataRow myDatarow;
DataSet dataSet1 = new DataSet();
SqlDataAdapter dataAdapter1;
SqlConnection conn1 = new SqlConnection(DSN);
dataAdapter1= new SqlDataAdapter(Sql,conn1);
dataAdapter1.Fill(dataSet1,"table1"); try
{
myDatarow = dataSet1.Tables["table1"].Rows[0];
}
catch
{
myDatarow = null;
}
return myDatarow;
}
SqlCommand mycmd=new SqlCommand(mystr,conn);
DataReader mydr;
mydr=mycmd.ExecuteReader();
mydr.Reader();
string pd=mydr[icount].Tostring;
mydr.Close;
if(pd=="0")
{
//插入代码;
}