查找有无相同数据库名，进入了死循环，谁知道解决方法呀？

Question

 谁知道有没有类似判断文件是否存在，那种简单的判断语句呀？                               //查找有无相同数据库名
                                foreach (object o in combox1.Items)
                                {
                                    if (o.ToString().Trim().Equals(combox1.Text.Trim()))
                                    {
                                        frm_msg frm_ms = new frm_msg();
                                        cls_msg.msg = "有相同名字的数据库，请改用其他数据库名字！";
                                        frm_ms.Show();
                                        break;
                                    }
                                    else
                                    {
                                       // string itSysDb = textBox2.Text.Trim();                                        string MySQL = "use master;" +
                                        "IF DB_ID(N'MyDatabase') IS NOT NULL " +
                                        "DROP DATABASE MyDatabase;" +
                                        "CREATE DATABASE MyDatabase " +
                                        "ON(NAME=MyDatabase_dat,FILENAME=\"C:\\MyDatabase.mdf\",SIZE=5,MAXSIZE=10,FILEGROWTH=1) " +
                                        "LOG ON(NAME=MyDatabase_log,FILENAME=\"C:\\MyDatabase.ldf\",SIZE=2,MAXSIZE=5,FILEGROWTH=1)";                                        try
                                        {                                         
                                            SqlCommand MyCommand = new SqlCommand(MySQL, conn);
                                            MyCommand.Connection.Open();
                                            MyCommand.ExecuteNonQuery();
                                            MessageBox.Show("数据安装成功！", "提示", MessageBoxButtons.OK, MessageBoxIcon.Information); // 这个提示反复弹出                                            sdr.Close();
                                            conn.Close();
                                            break;
                                        }
                                        catch (Exception ex)
                                        {
                                            MessageBox.Show(ex.Message, "提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
                                        }                                        break;
                                    }
                                    
                                }

Answer 1

使用数据库操作类
绑定的是DataRowView
forearch(DataRow dr in comboBox1.Items){
if(dr[0].ToString().Equals(""))
{
break;
}
else
{break;}
}

Answer 2

我换了种方式，可就是红色区的代码有问题，select * from sysdatabases where name = 'itSys'这名在sql中查询是有记录的。哪位知道是错在哪里了呀？提示connectstring属性尚未初始化。
 
           try
            {
                SqlConnection conn = new SqlConnection("Server=" + textBox1.Text.Trim() + ";DataBase=master;uid=" + textBox3.Text.Trim() + ";pwd=" + textBox4.Text.Trim());
                                                             
              
                    SqlDataReader temDR = dbOp.getcom("select * from sysdatabases where name = 'itSys'");
                    bool ifcom = temDR.Read();
                    //必须用Read()方法读取数据
                    if (ifcom)
                    {
                        frm_msg frm_ms = new frm_msg();
                        cls_msg.msg = "有相同数据库名称，请改用其他名称！";
                        frm_ms.Show();
                    }                    else
                    {
                        string MySQL = "use master;" +
                        "IF DB_ID(N'MyDatabase') IS NOT NULL " +
                        "DROP DATABASE MyDatabase;" +
                        "CREATE DATABASE MyDatabase " +
                        "ON(NAME=MyDatabase_dat,FILENAME=\"C:\\MyDatabase.mdf\",SIZE=5,MAXSIZE=10,FILEGROWTH=1) " +
                        "LOG ON(NAME=MyDatabase_log,FILENAME=\"C:\\MyDatabase.ldf\",SIZE=2,MAXSIZE=5,FILEGROWTH=1)";                        SqlCommand MyCommand = new SqlCommand(MySQL, conn);
                        try
                        {
                            MyCommand.Connection.Open();
                            MyCommand.ExecuteNonQuery();
                            MessageBox.Show("成功创建数据库", "信息提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
                        }
                        catch (Exception ex)
                        {
                            MessageBox.Show(ex.Message, "信息提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
                        }
                        finally
                        {
                            conn.Close();
                        }
                    }
                
            }            catch (Exception ex)
            {
                MessageBox.Show(ex.Message, "提示", MessageBoxButtons.OK, MessageBoxIcon.Information);