C#:
如果转贴请注明出处
作者:fx_blog(CSDN)
日期:2005-4-27
//=========================查询===========================
<% @ Page Language="C#" debug=true %>
<% @ import namespace="System.Data"%>
<% @ import namespace="System.Data.OleDb"%>
<% @ import namespace="System.IO"%>
<script runat=server>
void btn_search(Object sender,EventArgs e)
{
string connstring="Provider=Microsoft.Jet.OLEDB.4.0;Data Source="+Server.MapPath("**.mdb")+";";
string selstring="select * from dbtable where username='"+TextBox1.Text+"'";
OleDbConnection conn=new OleDbConnection(conn);
OleDbCommand cmd=new OleDbCommand();
cmd.CommandText = selstring;
cmd.Connection = conn;
try
{
conn.Open();
OleDbDataReader reader=cmd.ExecuteReader();
if(reader.Read())
{
Label1.Text="查找成功";
}
else
{
Label1.Text="查询失败";
}
}
catch (OleDbException ex)
{
Response.Write(ex.Errors[0].Message);
}
}
</script>
<form runat=server>
<asp:TextBox id="TextBox1" runat=server />
<asp:Button id="btn_search" runat=server text="查询" onclick=btn_search />
</form>
//==========================添加,删除,=====================
<% @ Page Language="C#" debug=true %>
<% @ import namespace="System.Data"%>
<% @ import namespace="System.Data.OleDb"%>
<% @ import namespace="System.IO"%>
<script runat=server>
void add_search(Object sender,EventArgs e)
{
string connstring="Provider=Microsoft.Jet.OLEDB.4.0;Data Source="+Server.MapPath("**.mdb")+";";
string selstring="select * from dbtable where username='"+TextBox1.Text+"'";
OleDbConnection conn=new OleDbConnection(conn);
OleDbCommand cmd=new OleDbCommand();
cmd.CommandText = selstring;
cmd.Connection = conn;
try
{
conn.Open();
OleDbDataReader reader=cmd.ExecuteReader();
if (reader.Read())
{
Label1.Text="数据库中已经有该记录了,请用其他用户名!";
}
else
{
reader.Close();
string addstring="insert into [atable](username)"+"values('"+TextBox1.Text+"')";
cmd=new OleDbCommand();
cmd.CommandText=addstring;
cmd.Connection=conn;
cmd.ExecuteNonQuery();
Label1.Text="添加成功";
}
conn.Close();
}
catch(OleDbException ex)
{
Response.Write(ex.Errors[0].Message);
}
</script>
<form runat=server>
<asp:TextBox id="TextBox1" runat=server />
<asp:Button id="btn" text="添加" onclick="add_search" runat=server />
</form>
//===========================删除=更新===================
<% @ Page Language="C#" debug=true %>
<% @ import namespace="System.Data"%>
<% @ import namespace="System.Data.OleDb"%>
<% @ import namespace="System.IO"%>
<script runat=server>
void add_search(Object sender,EventArgs e)
{
string connstring="Provider=Microsoft.Jet.OLEDB.4.0;Data Source="+Server.MapPath("**.mdb")+";";
string selstring="select * from dbtable where username='"+TextBox1.Text+"'";
OleDbConnection conn=new OleDbConnection(conn);
OleDbCommand cmd=new OleDbCommand();
cmd.CommandText = selstring;
cmd.Connection = conn;
try
{
conn.Open();
OleDbDataReader reader=cmd.ExecuteReader();
if (!reader.Read())
{
Label1.Text="数据库中没有该用户!";
}
else
{
reader.Close();
string addstring="delete * from atable where username='"+TextBox1.Text+"'";
// 如果是更新数据update * from atable where username='"+TextBox1.Text+"';
cmd=new OleDbCommand();
cmd.CommandText=addstring;
cmd.Connection=conn;
cmd.ExecuteNonQuery();
Label1.Text="操作成功";
}
conn.Close();
}
catch(OleDbException ex)
{
Response.Write(ex.Errors[0].Message);
}
</script>
<form runat=server>
<asp:TextBox id="TextBox1" runat=server />
<asp:Button id="btn" text="执行" onclick="add_search" runat=server />
</form>