if(查询数据库中是否有数据) 若有 select count(1) from a where { return false } else { 插入数据 }
StringBuilder SB = new StringBuilder(); string sql = string.Format("select * from qqq where Name='{0}'",Name); SqlCommand comm = new SqlCommand(sql,conn); SqlDataReader da = comm.ExecuteReader(); if(da.Read()){ if (Name.Equals(da["Name"].ToString())) { Console.WriteLine("用户名已注册!!!"); } } else { SB.AppendFormat("insert into qqq values('{0}','{1}')", Name, Pwd); SqlCommand co = new SqlCommand(Convert.ToString(SB), conn); Console.WriteLine("用户名不相同!");
{
return false
}
else
{
插入数据
}
string sql = string.Format("select * from qqq where Name='{0}'",Name);
SqlCommand comm = new SqlCommand(sql,conn);
SqlDataReader da = comm.ExecuteReader();
if(da.Read()){
if (Name.Equals(da["Name"].ToString()))
{ Console.WriteLine("用户名已注册!!!");
}
}
else
{
SB.AppendFormat("insert into qqq values('{0}','{1}')", Name, Pwd);
SqlCommand co = new SqlCommand(Convert.ToString(SB), conn); Console.WriteLine("用户名不相同!");
}
是这样?