C#数据库数据导入导出系列之四 WinForm数据库导入导出到Excel

C#数据库数据导入导出系列之四 WinForm数据库导入导出到Excel

在日常的项目中，Excel，Word，txt等格式的数据导入到数据库中是很常见的，我在这里做一下总结

这里将分为Asp.net导入Sql Server，Oracle数据库和WinForm导入Sql Server，Oracle数据库。

这里将的数据库数据库导入导出，其实对Sql Server 和Oracle都是通用的

如果使用ADO.Net连接Oracle数据库，需要在引用里添加“System.Data.OracleClient ”，其他方面与连接Sql Server数据库是一样的

SqlConnection cn = new SqlConnection();
OracleConnection oraleCn = new OracleConnection();

如果使用诸如Ibatis等持久层框架的话，唯一的区别就是在数据库连接语句上的差别而已。下面是两个例子

Oracle：Data Source=192.168.0.11/Contact;User ID=system;Password=ss;Unicode=True

Sql Server： Data Source=Contact；Server=localhost；uid=sa；pwd=ss

1，数据库导出到Excel

先看界面

然后是代码

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Diagnostics;
using Microsoft.Office.Interop.Excel;
using System.Reflection;
using System.IO;
using System.Data.SqlClient;
using System.Data.OracleClient;

namespace SqlServer__Excel
{
    public partial class SqlDB_To_Excel : Form
    {
        public SqlDB_To_Excel()
        {
            InitializeComponent();
        }

        private Microsoft.Office.Interop.Excel.Application myExcel = null;

        private void button1_Click(object sender, EventArgs e)
        {
            print(dataGridView1);
        }

        public void print(DataGridView dataGridView1)
        {
            //导出到execl   
            try
            {
                SaveFileDialog saveFileDialog = new SaveFileDialog();
                saveFileDialog.Filter = "导出Excel (*.xls)|*.xls";
                saveFileDialog.FilterIndex = 0;
                saveFileDialog.RestoreDirectory = true;
                saveFileDialog.CreatePrompt = true;
                saveFileDialog.Title = "导出文件保存路径";
                saveFileDialog.ShowDialog();
                string strName = saveFileDialog.FileName;
                if(strName.Length != 0)
                {
                    //没有数据的话就不往下执行   
                    if(dataGridView1.Rows.Count == 0)
                        return;

                    // toolStripProgressBar1.Visible = true;
                    System.Reflection.Missing miss = System.Reflection.Missing.Value;
                    //实例化一个Excel.Application对象
                    Microsoft.Office.Interop.Excel.Application excel = new Microsoft.Office.Interop.Excel.Application();
                    excel.Application.Workbooks.Add(true);
                    excel.Visible = false;//若是true，则在导出的时候会显示EXcel界面。
                    if(excel == null)
                    {
                        MessageBox.Show("EXCEL无法启动！", "错误", MessageBoxButtons.OK, MessageBoxIcon.Error);
                        return;
                    }
                    Microsoft.Office.Interop.Excel.Workbooks books = (Microsoft.Office.Interop.Excel.Workbooks)excel.Workbooks;
                    Microsoft.Office.Interop.Excel.Workbook book = (Microsoft.Office.Interop.Excel.Workbook)(books.Add(miss));
                    Microsoft.Office.Interop.Excel.Worksheet sheet = (Microsoft.Office.Interop.Excel.Worksheet)book.ActiveSheet;
                    sheet.Name = "test";
                    int m = 0, n = 0;
                    //生成Excel中列头名称   
                    for(int i = 0; i < dataGridView1.Columns.Count; i++)
                    {
                        excel.Cells[1, i + 1] = dataGridView1.Columns[i].HeaderText;//输出DataGridView列头名
                    }
                    //把DataGridView当前页的数据保存在Excel中   
                    for(int i = 0; i < dataGridView1.Rows.Count - 1; i++)
                    {
                        for(int j = 0; j < dataGridView1.Columns.Count; j++)
                        {
                            if(dataGridView1[j, i].ValueType == typeof(string))
                            {
                                excel.Cells[i + 2, j + 1] = "'" + dataGridView1[j, i].Value.ToString();
                            }
                            else
                            {
                                excel.Cells[i + 2, j + 1] = dataGridView1[j, i].Value.ToString();
                            }
                        }
                    }
                    sheet.SaveAs(strName, miss, miss, miss, miss, miss, Microsoft.Office.Interop.Excel.XlSaveAsAccessMode.xlNoChange, miss, miss, miss);
                    book.Close(false, miss, miss);
                    books.Close();
                    excel.Quit();
                    System.Runtime.InteropServices.Marshal.ReleaseComObject(sheet);
                    System.Runtime.InteropServices.Marshal.ReleaseComObject(book);
                    System.Runtime.InteropServices.Marshal.ReleaseComObject(books);
                    System.Runtime.InteropServices.Marshal.ReleaseComObject(excel);
                    GC.Collect();
                    MessageBox.Show("数据已经成功导出!", "提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
                    // toolStripProgressBar1.Value = 0;
                    System.Diagnostics.Process.Start(strName);
                }
            }
            catch(Exception ex)
            {
                MessageBox.Show(ex.Message, "错误提示");
            }
        }

        public void printAll(System.Data.DataTable dt)
        {
            //导出到execl
            try
            {
                 SaveFileDialog saveFileDialog = new SaveFileDialog();
                saveFileDialog.Filter = "导出Excel (*.xls)|*.xls";
                saveFileDialog.FilterIndex = 0;
                saveFileDialog.RestoreDirectory = true;
                saveFileDialog.CreatePrompt = true;
                saveFileDialog.Title = "导出文件保存路径";
                saveFileDialog.ShowDialog();
                string strName = saveFileDialog.FileName;
                if(strName.Length != 0)
                {
                    //没有数据的话就不往下执行
                    if(dt.Rows.Count == 0)
                        return;

                    // toolStripProgressBar1.Visible = true;
                    System.Reflection.Missing miss = System.Reflection.Missing.Value;
                    //实例化一个Excel.Application对象
                    Microsoft.Office.Interop.Excel.Application excel = new Microsoft.Office.Interop.Excel.Application();
                    excel.Application.Workbooks.Add(true);
                    excel.Visible = false;//若是true，则在导出的时候会显示EXcel界面。
                    if(excel == null)
                    {
                        MessageBox.Show("EXCEL无法启动！", "错误", MessageBoxButtons.OK, MessageBoxIcon.Error);
                        return;
                    }
                    Microsoft.Office.Interop.Excel.Workbooks books = (Microsoft.Office.Interop.Excel.Workbooks)excel.Workbooks;
                    Microsoft.Office.Interop.Excel.Workbook book = (Microsoft.Office.Interop.Excel.Workbook)(books.Add(miss));
                    Microsoft.Office.Interop.Excel.Worksheet sheet = (Microsoft.Office.Interop.Excel.Worksheet)book.ActiveSheet;
                    sheet.Name = "test";
                    int m = 0, n = 0;


                    //生成Excel中列头名称
                    for(int i = 0; i < dt.Columns.Count; i++)
                    {
                        excel.Cells[1, i + 1] = dataGridView1.Columns[i].HeaderText;//输出DataGridView列头名
                    }

                    //把DataGridView当前页的数据保存在Excel中
                    if(dt.Rows.Count > 0)
                    {
                        for(int i = 0; i < dt.Rows.Count; i++)//控制Excel中行，上下的距离，就是可以到Excel最下的行数，比数据长了报错，比数据短了会显示不完
                        {
                            for(int j = 0; j < dt.Columns.Count; j++)//控制Excel中列，左右的距离，就是可以到Excel最右的列数，比数据长了报错，比数据短了会显示不完
                            {
                                string str = dt.Rows[i][j].ToString();
                                excel.Cells[i + 2, j + 1] = "'" + str;//i控制行，从Excel中第2行开始输出第一行数据，j控制列，从Excel中第1列输出第1列数据，"'" +是以string形式保存，所以遇到数字不会转成16进制
                            }
                        }
                    }
                    sheet.SaveAs(strName, miss, miss, miss, miss, miss, Microsoft.Office.Interop.Excel.XlSaveAsAccessMode.xlNoChange, miss, miss, miss);
                    book.Close(false, miss, miss);
                    books.Close();
                    excel.Quit();
                    System.Runtime.InteropServices.Marshal.ReleaseComObject(sheet);
                    System.Runtime.InteropServices.Marshal.ReleaseComObject(book);
                    System.Runtime.InteropServices.Marshal.ReleaseComObject(books);
                    System.Runtime.InteropServices.Marshal.ReleaseComObject(excel);

                    GC.Collect();
                    MessageBox.Show("数据已经成功导出!", "提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
                    // toolStripProgressBar1.Value = 0;
                    System.Diagnostics.Process.Start(strName);
                }
            }
            catch(Exception ex)
            {
                MessageBox.Show(ex.Message, "错误提示");
            }
        }

        private void SqlDB_To_Excel_Load(object sender, EventArgs e)
        {
            dataGridView1.DataSource = GetDataTableFromSqlServer();
        }

        private void button2_Click(object sender, EventArgs e)
        {
            printAll(GetDataTableFromSqlServer());
        }

        private System.Data.DataTable GetDataTableFromSqlServer()
        {
            string sqlconn = "database=database1;server=localhost;uid=sa;pwd=sa";
            SqlConnection cn = new SqlConnection(sqlconn);
            string cmdText = "select * from users";
            SqlDataAdapter da = new SqlDataAdapter(cmdText, cn);
            DataSet ds = new DataSet();
            da.Fill(ds, "table1");
            return ds.Tables[0];
        }

        private System.Data.DataTable GetDataTableFromOracle()
        {
            string oracleconn = "Data Source=192.168.2.105/Database1;User ID=system;Password=ss;Unicode=True";
            OracleConnection cn = new OracleConnection(oracleconn);
            string cmdText = "select * from users";
            OracleDataAdapter da = new OracleDataAdapter(cmdText, cn);
            DataSet ds = new DataSet();
            da.Fill(ds, "table1");
            return ds.Tables[0];
        }
    }
}

结果：

代码的思想就是将数据从数据库中读出到DataTable或者DataGridView中，然后遍历他们的每一个单元格的值，给Excel对应的单元格赋值。

使用DataTable作为遍历的对象，是为了去除分页的困扰。

看到这里，如果换一个List<T>对象集合，也应该能导出到数据库中了。

2，Excel数据导入到数据库

在WinForm中Excel导入到数据库中和在WebForm中的导入过程是一样的。可参见前面的内容。