未处理 System.Data.SqlClient.SqlException Message=数据库中已存在名为 'hy_Linshibiao' 的对象.

using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Data;

using System.Data.SqlClient;

using System.Drawing;

using System.Linq;

using System.Text;

using System.Windows.Forms;



namespace WindowsFormsApplication2

{

    public partial class Form1 : Form

    {

        string strDatabase = null;

        public Form1()

        {

            InitializeComponent();

        }



        private DataTable Database()

        {

            using(SqlConnection conn=new SqlConnection("server=localhost;database=master;uid=sa;pwd=chy19900909"))

            {

                SqlDataAdapter da = new SqlDataAdapter("select name from sysdatabases",conn);

                DataTable dt = new DataTable("sysdatabases");

                da.Fill(dt);

                return dt;

            }

        }

        private void Form1_Load(object sender, EventArgs e)

        {

            comboBox1.DataSource = Database();

            comboBox1.DisplayMember = "name";

            comboBox1.ValueMember = "name";

        }



        private void button1_Click(object sender, EventArgs e)

        {

            this.dataGridView1.DataSource=null;

            strDatabase = this.comboBox1.Text.ToString();

            using(SqlConnection conn=new SqlConnection("server=localhost;database='"+strDatabase+"';uid=sa;pwd=chy19900909"))

            {

                SqlDataAdapter da = new SqlDataAdapter("select name from sysobjects where type='U' and name<>'dtproperties'",conn);

                DataTable dt = new DataTable("sysobjects");

                da.Fill(dt);

                listBox1.DataSource = dt.DefaultView;

                listBox1.DisplayMember = "name";

                listBox1.ValueMember="name";



            }



        }



      

        private void listBox1_Click(object sender, EventArgs e)

        {

            string strTableName = this.listBox1.SelectedValue.ToString();

            using(SqlConnection conn=new SqlConnection("server=localhost;database='"+strDatabase+"';uid=sa;pwd=chy19900909"))

            {

                string strSql = "select  name 字段名, xusertype 类型编号, length 长度 into hy_Linshibiao from  syscolumns  where id=object_id('" + strTableName + "') ";

                strSql += "select name 类型,xusertype 类型编号 into angel_Linshibiao from systypes where xusertype in (select xusertype from syscolumns where id=object_id('" + strTableName + "'))";

                conn.Open();

                SqlCommand cmd = new SqlCommand(strSql, conn);

                cmd.ExecuteNonQuery();

                conn.Close();



                SqlDataAdapter da = new SqlDataAdapter("select 字段名,类型,长度 from hy_Linshibiao t,angel_Linshibiao b where t.类型编号=b.类型编号", conn);

                DataTable dt = new DataTable();

                da.Fill(dt);

                this.dataGridView1.DataSource = dt.DefaultView;



                SqlCommand cmdnew = new SqlCommand("drop table hy_Linshibiao,angel_Linshibiao", conn);

                conn.Open();

                cmdnew.ExecuteNonQuery();

                conn.Close();

            

            }



        }



       

     

    }

}

补充：.NET技术 ,  C#

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