private bool UserExits(string username)
{
SqlConnection myConnection = new SqlConnection(
ConfigurationManager.ConnectionStrings["SQLCONNECTIONSTRING"].ConnectionString);
string str = "select Name from [o] where Name='" + username + "'";
SqlCommand myCommand = new SqlCommand(str, myConnection);
try
{
myConnection.Open();
SqlDataReader dr = myCommand.ExecuteReader();
if (dr.Read()) { return true; }//这里为什么总是返回true?我没注册过的用户名,dr.Read()也为真,这是怎么回事?
else return false;
}
catch (SqlException ex)
{
throw new Exception(ex.Message, ex);
}
finally { myConnection.Close(); }
}
{
SqlConnection myConnection = new SqlConnection(
ConfigurationManager.ConnectionStrings["SQLCONNECTIONSTRING"].ConnectionString);
string str = "select Name from [o] where Name='" + username + "'";
SqlCommand myCommand = new SqlCommand(str, myConnection);
try
{
myConnection.Open();
SqlDataReader dr = myCommand.ExecuteReader();
if (dr.Read()) { return true; }//这里为什么总是返回true?我没注册过的用户名,dr.Read()也为真,这是怎么回事?
else return false;
}
catch (SqlException ex)
{
throw new Exception(ex.Message, ex);
}
finally { myConnection.Close(); }
}
return dr.Read()
Label1.Text = "用户已经存在"
ads1.Close()
Else
ads1.Close()
Dim ads As SqlDataReader = scmd.ExecuteReader() End If
vb。net代码看看有永不?