private void btnlogin_click(object sender, eventargs e)
{
string username = txtusername.text;
string userpwd = txtuserpwd.text;
string sql = “select * from userinfo where username = @username and userpwd = @userpwd”;
sqlparameter[] param =
{
new sqlparameter(“@username”,sqldbtype.varchar),
new sqlparameter(“@userpwd”,sqldbtype.varchar)
};
param[0].value = username;
param[1].value = userpwd;
dataset ds = datamanager.get(sql, param);
if (ds.tables.count > 0)
{
this.hide();
frmmain main = new frmmain();
main.show();
}
else
{
messagebox.show(“登录失败！”, “提示”, messageboxbuttons.abortretryignore, messageboxicon.hand);
}
}
datamanager类：
public static dataset get(string sql, sqlparameter[] pars)
{
return new dataservice().get(sql, pars);
}
dataservice类：
public dataset get(string sql, sqlparameter[] pars)
{
init(sql, pars, syscontrol.connectionstring);
return get();
}
private dataset get()
{
sqldataadapter da = new sqldataadapter();
da.selectcommand = cmd;
dataset ds = new dataset();
try
{
da.fill(ds);
}
catch (system.exception)
{
//throw;
}
con.close();
return ds;
}
syscontrol类：
/// <summary>
/// 数据库连接字符串
/// </summary>
public static string connectionstring = configurationmanager.appsettings[“connectionstring”];
在app配置文件里面添加链接：
<appsettings>
<add key =”connectionstring” value=”server=.;user id=sa; password=123456; database=db;”/>
</appsettings>