简单的控制台学习资料，SQL查询器


using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data;
using System.Data.SqlClient;
using System.Diagnostics;namespace Sql查询器
{
    class Program
    {
        private static string ServerName = "";
        private static string LoginDataBaseName = "";
        private static string LoginUserName = "";
        private static string LoginPwd = "";        private static SqlConnection Connect = null;        static void Main(string[] args)
        {
            Console.Title = "SQL简单查询器";
            ServerName = Init("服务器地址");
            LoginDataBaseName = Init("服务库名称");
            LoginUserName = Init("登陆用户名");
            LoginPwd = Init("登陆用户口令");
            OpenConnect();            
        }        static void ExecuteSql()
        {            goto Sql;
        Sql:
            {
                Console.Write("SQL:");
                string value = Console.ReadLine();
                if (value == null || value.Trim() == "")
                {
                    goto Sql;
                }
                try
                {
                    Stopwatch watch = new Stopwatch();
                    watch.Start();
                    DateTime BeginTime = DateTime.Now;
                    SqlCommand cmd = new SqlCommand(value, Connect);
                    SqlDataAdapter da = new SqlDataAdapter(cmd);
                    DataTable SqlTable = new DataTable();
                    da.Fill(SqlTable);
                    watch.Stop();
                    Console.WriteLine("总共耗时:" + watch.Elapsed.ToString() + " 记录条数:" + SqlTable.Rows.Count);
                    
                    StringBuilder Cols = new StringBuilder();
                    Cols.Append("No ");
                    for (int c = 0; c < SqlTable.Columns.Count; c++)
                    {
                        Cols.Append(SqlTable.Columns[c].ColumnName + " ");                       
                    }                    
                    Console.WriteLine(Cols.ToString().Trim());
           
                    for (int r = 0; r < SqlTable.Rows.Count; r++)
                    {
                        StringBuilder Rows = new StringBuilder();
                        Rows.Append(Convert.ToInt32(r + 1) + " ");
                        for (int c = 0; c < SqlTable.Columns.Count; c++)
                        {
                            if (SqlTable.Rows[r][c] != DBNull.Value)
                            {
                                Rows.Append(SqlTable.Rows[r][c].ToString() + " ");
                            }
                            else
                            {
                                Rows.Append("NULL ");
                            }
                        }
                        Console.WriteLine(Rows.ToString().Trim());
                    }
                    Console.WriteLine("");
                    goto Sql;
                }
                catch (Exception e)
                {
                    Console.WriteLine(e.Message);
                    goto Sql;
                }
            }
        }                static void OpenConnect()
        {
            if (ServerName == null || ServerName.Trim() == "")
            {
                ServerName = Init("服务器地址");
            }
            if (LoginDataBaseName == null || LoginDataBaseName.Trim() == "")
            {
                LoginDataBaseName = Init("服务器地址");
            }
            string strconnect = "Data Source=" + ServerName + ";Initial Catalog=" + LoginDataBaseName + ";User ID=" + LoginUserName + ";Password=" + LoginPwd + ";Integrated Security=false;Connect Timeout=15;";
            if (Connect == null)
            {
                Connect = new SqlConnection(strconnect);
            }
            if (Connect.State != ConnectionState.Closed)
            {
                try
                {
                    Connect.Close();
                }
                catch { }
            }
            Connect.ConnectionString = strconnect;
            try
            {
                Console.WriteLine("正在连接数据服务器,请候候...");
                Connect.Open();
                Console.Clear();
                ExecuteSql();
            }
            catch (Exception e)
            {
                Console.WriteLine(e.Message);
                if (e.Message.Contains("provider: Named Pipes Provider, error: 40") == true)
                {
                    ServerName = Init("服务器地址");
                    LoginDataBaseName = Init("服务器地址");
                }
                LoginUserName = Init("登陆用户名");
                LoginPwd = Init("登陆用户口令");
                OpenConnect();
            }
        }        static string Init(string Name)
        {
            goto config;
        config:
            {
                Console.Write(Name + "：");
                string value = Console.ReadLine();
                if (value == null || value.Trim() == "")
                {
                    Console.WriteLine(Name + "不能为空,请重新输入!");
                    goto config;
                }
                return value;
            }
        }    }
}