DataGridView导出到Excel的三个方法

原文出处：http://www.yongfa365.com/Item/DataGridViewToExcel.html

#region DataGridView数据显示到Excel
/// <summary> 
/// 打开Excel并将DataGridView控件中数据导出到Excel
/// </summary> 
/// <param name="dgv">DataGridView对象 </param> 
/// <param name="isShowExcle">是否显示Excel界面 </param> 
/// <remarks>
/// add com "Microsoft Excel 11.0 Object Library"
/// using Excel=Microsoft.Office.Interop.Excel;
/// </remarks>
/// <returns> </returns> 
public bool DataGridviewShowToExcel(DataGridView dgv, bool isShowExcle)
{
    if (dgv.Rows.Count == 0)
        return false;
    //建立Excel对象 
    Excel.Application excel = new Excel.Application();
    excel.Application.Workbooks.Add(true);
    excel.Visible = isShowExcle;
    //生成字段名称 
    for (int i = 0; i < dgv.ColumnCount; i++)
    {
        excel.Cells[1, i + 1] = dgv.Columns[i].HeaderText;
    }
    //填充数据 
    for (int i = 0; i < dgv.RowCount - 1; i++)
    {
        for (int j = 0; j < dgv.ColumnCount; j++)
        {
            if (dgv[j, i].ValueType == typeof(string))
            {
                excel.Cells[i + 2, j + 1] = "'" + dgv[j, i].Value.ToString();
            }
            else
            {
                excel.Cells[i + 2, j + 1] = dgv[j, i].Value.ToString();
            }
        }
    }
    return true;
}
#endregion 

#region DateGridView导出到csv格式的Excel
/// <summary>
/// 常用方法，列之间加\t，一行一行输出，此文件其实是csv文件，不过默认可以当成Excel打开。
/// </summary>
/// <remarks>
/// using System.IO;
/// </remarks>
/// <param name="dgv"></param>
private void DataGridViewToExcel(DataGridView dgv)
{
    SaveFileDialog dlg = new SaveFileDialog();
    dlg.Filter = "Execl files (*.xls)|*.xls";
    dlg.FilterIndex = 0;
    dlg.RestoreDirectory = true;
    dlg.CreatePrompt = true;
    dlg.Title = "保存为Excel文件";

    if (dlg.ShowDialog() == DialogResult.OK)
    {
        Stream myStream;
        myStream = dlg.OpenFile();
        StreamWriter sw = new StreamWriter(myStream, System.Text.Encoding.GetEncoding(-0));
        string columnTitle = "";
        try
        {
            //写入列标题
            for (int i = 0; i < dgv.ColumnCount; i++)
            {
                if (i > 0)
                {
                    columnTitle += "\t";
                }
                columnTitle += dgv.Columns[i].HeaderText;
            }
            sw.WriteLine(columnTitle);

            //写入列内容
            for (int j = 0; j < dgv.Rows.Count; j++)
            {
                string columnValue = "";
                for (int k = 0; k < dgv.Columns.Count; k++)
                {
                    if (k > 0)
                    {
                        columnValue += "\t";
                    }
                    if (dgv.Rows[j].Cells[k].Value == null)
                        columnValue += "";
                    else
                        columnValue += dgv.Rows[j].Cells[k].Value.ToString().Trim();
                }
                sw.WriteLine(columnValue);
            }
            sw.Close();
            myStream.Close();
        }
        catch (Exception e)
        {
            MessageBox.Show(e.ToString());
        }
        finally
        {
            sw.Close();
            myStream.Close();
        }
    }
} 
#endregion

#region DataGridView导出到Excel，有一定的判断性
/// <summary> 
///方法，导出DataGridView中的数据到Excel文件 
/// </summary> 
/// <remarks>
/// add com "Microsoft Excel 11.0 Object Library"
/// using Excel=Microsoft.Office.Interop.Excel;
/// using System.Reflection;
/// </remarks>
/// <param name= "dgv"> DataGridView </param> 
public static void DataGridViewToExcel(DataGridView dgv)
{


    #region   验证可操作性

    //申明保存对话框 
    SaveFileDialog dlg = new SaveFileDialog();
    //默然文件后缀 
    dlg.DefaultExt = "xls ";
    //文件后缀列表 
    dlg.Filter = "EXCEL文件(*.XLS)|*.xls ";
    //默然路径是系统当前路径 
    dlg.InitialDirectory = Directory.GetCurrentDirectory();
    //打开保存对话框 
    if (dlg.ShowDialog() == DialogResult.Cancel) return;
    //返回文件路径 
    string fileNameString = dlg.FileName;
    //验证strFileName是否为空或值无效 
    if (fileNameString.Trim() == " ")
    { return; }
    //定义表格内数据的行数和列数 
    int rowscount = dgv.Rows.Count;
    int colscount = dgv.Columns.Count;
    //行数必须大于0 
    if (rowscount <= 0)
    {
        MessageBox.Show("没有数据可供保存 ", "提示 ", MessageBoxButtons.OK, MessageBoxIcon.Information);
        return;
    }

    //列数必须大于0 
    if (colscount <= 0)
    {
        MessageBox.Show("没有数据可供保存 ", "提示 ", MessageBoxButtons.OK, MessageBoxIcon.Information);
        return;
    }

    //行数不可以大于65536 
    if (rowscount > 65536)
    {
        MessageBox.Show("数据记录数太多(最多不能超过65536条)，不能保存 ", "提示 ", MessageBoxButtons.OK, MessageBoxIcon.Information);
        return;
    }

    //列数不可以大于255 
    if (colscount > 255)
    {
        MessageBox.Show("数据记录行数太多，不能保存 ", "提示 ", MessageBoxButtons.OK, MessageBoxIcon.Information);
        return;
    }

    //验证以fileNameString命名的文件是否存在，如果存在删除它 
    FileInfo file = new FileInfo(fileNameString);
    if (file.Exists)
    {
        try
        {
            file.Delete();
        }
        catch (Exception error)
        {
            MessageBox.Show(error.Message, "删除失败 ", MessageBoxButtons.OK, MessageBoxIcon.Warning);
            return;
        }
    }
    #endregion
    Excel.Application objExcel = null;
    Excel.Workbook objWorkbook = null;
    Excel.Worksheet objsheet = null;
    try
    {
        //申明对象 
        objExcel = new Microsoft.Office.Interop.Excel.Application();
        objWorkbook = objExcel.Workbooks.Add(Missing.Value);
        objsheet = (Excel.Worksheet)objWorkbook.ActiveSheet;
        //设置EXCEL不可见 
        objExcel.Visible = false;

        //向Excel中写入表格的表头 
        int displayColumnsCount = 1;
        for (int i = 0; i <= dgv.ColumnCount - 1; i++)
        {
            if (dgv.Columns[i].Visible == true)
            {
                objExcel.Cells[1, displayColumnsCount] = dgv.Columns[i].HeaderText.Trim();
                displayColumnsCount++;
            }
        }
        //设置进度条 
        //tempProgressBar.Refresh(); 
        //tempProgressBar.Visible   =   true; 
        //tempProgressBar.Minimum=1; 
        //tempProgressBar.Maximum=dgv.RowCount; 
        //tempProgressBar.Step=1; 
        //向Excel中逐行逐列写入表格中的数据 
        for (int row = 0; row <= dgv.RowCount - 1; row++)
        {
            //tempProgressBar.PerformStep(); 

            displayColumnsCount = 1;
            for (int col = 0; col < colscount; col++)
            {
                if (dgv.Columns[col].Visible == true)
                {
                    try
                    {
                        objExcel.Cells[row + 2, displayColumnsCount] = dgv.Rows[row].Cells[col].Value.ToString().Trim();
                        displayColumnsCount++;
                    }
                    catch (Exception)
                    {

                    }

                }
            }
        }
        //隐藏进度条 
        //tempProgressBar.Visible   =   false; 
        //保存文件 
        objWorkbook.SaveAs(fileNameString, Missing.Value, Missing.Value, Missing.Value, Missing.Value,
                Missing.Value, Excel.XlSaveAsAccessMode.xlShared, Missing.Value, Missing.Value, Missing.Value,
                Missing.Value, Missing.Value);
    }
    catch (Exception error)
    {
        MessageBox.Show(error.Message, "警告 ", MessageBoxButtons.OK, MessageBoxIcon.Warning);
        return;
    }
    finally
    {
        //关闭Excel应用 
        if (objWorkbook != null) objWorkbook.Close(Missing.Value, Missing.Value, Missing.Value);
        if (objExcel.Workbooks != null) objExcel.Workbooks.Close();
        if (objExcel != null) objExcel.Quit();

        objsheet = null;
        objWorkbook = null;
        objExcel = null;
    }
    MessageBox.Show(fileNameString + "\n\n导出完毕! ", "提示 ", MessageBoxButtons.OK, MessageBoxIcon.Information);

}

#endregion