你的插入语句不对啊,
string str1="insert into dl where NAME='"+txtname.Text+"'";
应该该为
string str1="insert into dl(name) value ('"+txtname.Text+"')";
string str1="insert into dl where NAME='"+txtname.Text+"'";
应该该为
string str1="insert into dl(name) value ('"+txtname.Text+"')";
private void button1_Click(object sender, System.EventArgs e)
{
string str="select NAME from dl where NAME='"+txtname.Text+"'";
string str1="insert into dl values('"+txtname.Text+"')";
OleDbConnection conn=new OleDbConnection("Provider=MSDAORA;Password=zxm;User ID=Zxm;Data Source=zxm.acme.com");
OleDbCommand comm=new OleDbCommand(str,conn);
OleDbDataReader datareader=null;
conn.Open();
datareader=comm.ExecuteReader();
if(datareader.Read()==true)
{
MessageBox.Show("用户名已存在,请重新选择");
}
else if(txtname.Text=="")
{
MessageBox.Show("姓名不能为空"); }
else
{
datareader.Close();
int a=comm.ExecuteNonQuery();
if(a>0)
{
DataSet dataset=new DataSet();
OleDbDataAdapter adapter=new OleDbDataAdapter(str1,conn);
adapter.Fill(dataset,"dl");
DataTable datatable1=null;
DataRow datarow1=null;
datatable1=dataset.Tables["dl"];
datarow1=datatable1.NewRow();
datarow1["NAME"]=txtname.Text;
datatable1.Rows.Add(datarow1);
}
else
{
MessageBox.Show("插入不成功");
}
//OleDbDataAdapter adapter=new OleDbDataAdapter(str1,conn);
//adapter.InsertCommand=new OleDbCommand(str1,conn);
}
conn.Close(); }
}
}
->
string str1="insert into dl (NAME) values('"+txtname.Text+"')";