问题：最近在项目中遇到，不同客户机安装不同Office版本，在导出Excel时，发生错误。
找不到Excel Com组件，错误信息如下。
未能加载文件或程序集“Microsoft.Office.Interop.Excel, Version=12.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c”或它的某一个依赖项。系统找不到指定的文件。
解决方法：
1.引用高版本的的Excel.dll组件，最新版本14.0.0 防止客户安装高版本如Office不能导出。
（DLL组件可以兼容低版本，不能兼容高版本）
2.右键DLL属性，将引用的Excel.dll组件，嵌入互操作类型为True，特定版本=false .这一步非常关键。
嵌入互操作类型 改成True后，生成时可能现有调用Excel的代码会报错，引用Microsoft.CSharp 命名空间，可以解决此问题。
3.引用Excel 14.0.0 DLL组件方法，vs2012 右键添加引用->程序集->扩展->Microsoft.Office.Interop.Excel
Excel.dll http://files.cnblogs.com/files/ichk/Microsoft.Office.Interop.Excel.rar
其他方法：
1.使用NPOI.DLL开源组件，可以不安装Office软件，进行读写Excel文件。
NPIO.dll http://files.cnblogs.com/files/ichk/NPOI.rar
调用方法如下：
导出代码：
/// <summary>
/// DataTable导出到Excel的MemoryStream Export()
/// </summary>
/// <param name="dtSource">DataTable数据源</param>
/// <param name="strHeaderText">Excel表头文本（例如：车辆列表）</param>
public static MemoryStream Export(DataTable dtSource, string strHeaderText)
{
HSSFWorkbook workbook = new HSSFWorkbook();
ISheet sheet = workbook.CreateSheet();
#region 右击文件 属性信息
{
DocumentSummaryInformation dsi = PropertySetFactory.CreateDocumentSummaryInformation();
dsi.Company = "NPOI";
workbook.DocumentSummaryInformation = dsi;
SummaryInformation si = PropertySetFactory.CreateSummaryInformation();
si.Author = "文件作者信息"; //填加xls文件作者信息
si.ApplicationName = "创建程序信息"; //填加xls文件创建程序信息
si.LastAuthor = "最后保存者信息"; //填加xls文件最后保存者信息
si.Comments = "作者信息"; //填加xls文件作者信息
si.Title = "标题信息"; //填加xls文件标题信息
si.Subject = "主题信息";//填加文件主题信息
si.CreateDateTime = System.DateTime.Now;
workbook.SummaryInformation = si;
}
#endregion
ICellStyle dateStyle = workbook.CreateCellStyle();
IDataFormat format = workbook.CreateDataFormat();
dateStyle.DataFormat = format.GetFormat("yyyy-mm-dd");
//取得列宽
int[] arrColWidth = new int[dtSource.Columns.Count];
foreach (DataColumn item in dtSource.Columns)
{
arrColWidth[item.Ordinal] = Encoding.GetEncoding(936).GetBytes(item.ColumnName.ToString()).Length;
}
for (int i = 0; i < dtSource.Rows.Count; i++)
{
for (int j = 0; j < dtSource.Columns.Count; j++)
{
int intTemp = Encoding.GetEncoding(936).GetBytes(dtSource.Rows[i][j].ToString()).Length;
if (intTemp > arrColWidth[j])
{
arrColWidth[j] = intTemp;
}
}
}
int rowIndex = 0;
foreach (DataRow row in dtSource.Rows)
{
#region 新建表，填充表头，填充列头，样式
if (rowIndex == 65535 || rowIndex == 0)
{
if (rowIndex != 0)
{
sheet = workbook.CreateSheet();
}
#region 表头及样式
{
IRow headerRow = sheet.CreateRow(0);
headerRow.HeightInPoints = 25;
headerRow.CreateCell(0).SetCellValue(strHeaderText);
ICellStyle headStyle = workbook.CreateCellStyle();
headStyle.Alignment = HorizontalAlignment.CENTER;
IFont font = workbook.CreateFont();
font.FontHeightInPoints = 20;
font.Boldweight = 700;
headStyle.SetFont(font);
headerRow.GetCell(0).CellStyle = headStyle;
sheet.AddMergedRegion(new NPOI.SS.Util.CellRangeAddress(0, 0, 0, dtSource.Columns.Count - 1));
}
#endregion
#region 列头及样式
{
IRow headerRow = sheet.CreateRow(1);
ICellStyle headStyle = workbook.CreateCellStyle();
headStyle.Alignment = HorizontalAlignment.CENTER;
IFont font = workbook.CreateFont();
font.FontHeightInPoints = 10;
font.Boldweight = 700;
headStyle.SetFont(font);
foreach (DataColumn column in dtSource.Columns)
{
headerRow.CreateCell(column.Ordinal).SetCellValue(column.ColumnName);
headerRow.GetCell(column.Ordinal).CellStyle = headStyle;
//设置列宽
sheet.SetColumnWidth(column.Ordinal, (arrColWidth[column.Ordinal] + 1) * 256);
}
}
#endregion
rowIndex = 2;
}
#endregion
#region 填充内容
IRow dataRow = sheet.CreateRow(rowIndex);
foreach (DataColumn column in dtSource.Columns)
{
ICell newCell = dataRow.CreateCell(column.Ordinal);
string drValue = row[column].ToString();
switch (column.DataType.ToString())
{
case "System.String"://字符串类型
newCell.SetCellValue(drValue);
break;
case "System.DateTime"://日期类型
System.DateTime dateV;
System.DateTime.TryParse(drValue, out dateV);
newCell.SetCellValue(dateV);
newCell.CellStyle = dateStyle;//格式化显示
break;
case "System.Boolean"://布尔型
bool boolV = false;
bool.TryParse(drValue, out boolV);
newCell.SetCellValue(boolV);
break;
case "System.Int16"://整型
case "System.Int32":
case "System.Int64":
case "System.Byte":
int intV = 0;
int.TryParse(drValue, out intV);
newCell.SetCellValue(intV);
break;
case "System.Decimal"://浮点型
case "System.Double":
double doubV = 0;
double.TryParse(drValue, out doubV);
newCell.SetCellValue(doubV);
break;
case "System.DBNull"://空值处理
newCell.SetCellValue("");
break;
default:
newCell.SetCellValue("");
break;
}
}
#endregion
rowIndex++;
}
using (MemoryStream ms = new MemoryStream())
{
workbook.Write(ms);
ms.Flush();
ms.Position = 0;
sheet.Dispose();
return ms;
}
}
导入：
/// <summary>
/// 读取excel ,默认第一行为标头
/// </summary>
/// <param name="strFileName">excel文档路径</param>
/// <returns></returns>
public static DataTable Import(string strFileName)
{
DataTable dt = new DataTable();
HSSFWorkbook hssfworkbook;
using (FileStream file = new FileStream(strFileName, FileMode.Open, FileAccess.Read))
{
hssfworkbook = new HSSFWorkbook(file);
}
ISheet sheet = hssfworkbook.GetSheetAt(0);
System.Collections.IEnumerator rows = sheet.GetRowEnumerator();
IRow headerRow = sheet.GetRow(0);
int cellCount = headerRow.LastCellNum;
for (int j = 0; j < cellCount; j++)
{
ICell cell = headerRow.GetCell(j);
dt.Columns.Add(cell.ToString());
}
for (int i = (sheet.FirstRowNum + 1); i <= sheet.LastRowNum; i++)
{
IRow row = sheet.GetRow(i);
DataRow dataRow = dt.NewRow();
for (int j = row.FirstCellNum; j < cellCount; j++)
{
if (row.GetCell(j) != null)
dataRow[j] = row.GetCell(j).ToString();
}
dt.Rows.Add(dataRow);
}
return dt;
}
2.使用C#发射方式调用Excel进行，不需要引用Excel.dll组件。此种方法不建议，太麻烦，也需要安装Office。
调用方法如下：
private void Export2Excel(DataGridView datagridview, bool captions)
{
object objApp_Late;
object objBook_Late;
object objBooks_Late;
object objSheets_Late;
object objSheet_Late;
object objRange_Late;
object[] Parameters;
string[] headers = new string[datagridview.DisplayedColumnCount(true)];
string[] columns = new string[datagridview.DisplayedColumnCount(true)];
string[] colName = new string[datagridview.DisplayedColumnCount(true)];
int i = 0;
int c = 0;
int m = 0;
for (c = 0; c < datagridview.Columns.Count; c++)
{
for (int j = 0; j < datagridview.Columns.Count; j++)
{
DataGridViewColumn tmpcol = datagridview.Columns[j];
if (tmpcol.DisplayIndex == c)
{
if (tmpcol.Visible) //不显示的隐藏列初始化为tag＝0
{
headers[c - m] = tmpcol.HeaderText;
i = c - m + 65;
columns[c - m] = Convert.ToString((char)i);
colName[c - m] = tmpcol.Name;
}
else
{
m++;
}
break;
}
}
}
try
{
// Get the class type and instantiate Excel.
Type objClassType;
objClassType = Type.GetTypeFromProgID("Excel.Application");
objApp_Late = Activator.CreateInstance(objClassType);
//Get the workbooks collection.
objBooks_Late = objApp_Late.GetType().InvokeMember("Workbooks", BindingFlags.GetProperty, null, objApp_Late, null);
//Add a new workbook.
objBook_Late = objBooks_Late.GetType().InvokeMember("Add", BindingFlags.InvokeMethod, null, objBooks_Late, null);
//Get the worksheets collection.
objSheets_Late = objBook_Late.GetType().InvokeMember("Worksheets", BindingFlags.GetProperty, null, objBook_Late, null);
//Get the first worksheet.
Parameters = new Object[1];
Parameters[0] = 1;
objSheet_Late = objSheets_Late.GetType().InvokeMember("Item", BindingFlags.GetProperty, null, objSheets_Late, Parameters);
if (captions)
{
// Create the headers in the first row of the sheet
for (c = 0; c < datagridview.DisplayedColumnCount(true); c++)
{
//Get a range object that contains cell.
Parameters = new Object[2];
Parameters[0] = columns[c] + "1";
Parameters[1] = Missing.Value;
objRange_Late = objSheet_Late.GetType().InvokeMember("Range", BindingFlags.GetProperty, null, objSheet_Late, Parameters);
//Write Headers in cell.
Parameters = new Object[1];
Parameters[0] = headers[c];
objRange_Late.GetType().InvokeMember("Value", BindingFlags.SetProperty, null, objRange_Late, Parameters);
}
}
// Now add the data from the grid to the sheet starting in row 2
for (i = 0; i < datagridview.RowCount; i++)
{
c = 0;
foreach (string txtCol in colName)
{
DataGridViewColumn col = datagridview.Columns[txtCol];
if (col.Visible)
{
//Get a range object that contains cell.
Parameters = new Object[2];
Parameters[0] = columns[c] + Convert.ToString(i + 2);
Parameters[1] = Missing.Value;
objRange_Late = objSheet_Late.GetType().InvokeMember("Range", BindingFlags.GetProperty, null, objSheet_Late, Parameters);
//Write Headers in cell.
Parameters = new Object[1];
//Parameters[0] = datagridview.Rows[i].Cells[headers[c]].Value.ToString();
Parameters[0] = datagridview.Rows[i].Cells[col.Name].Value.ToString();
objRange_Late.GetType().InvokeMember("Value", BindingFlags.SetProperty, null, objRange_Late, Parameters);
c++;
}
}
}
//Return control of Excel to the user.
Parameters = new Object[1];
Parameters[0] = true;
objApp_Late.GetType().InvokeMember("Visible", BindingFlags.SetProperty,
null, objApp_Late, Parameters);
objApp_Late.GetType().InvokeMember("UserControl", BindingFlags.SetProperty,
null, objApp_Late, Parameters);
}
catch (Exception theException)
{
String errorMessage;
errorMessage = "Error: ";
errorMessage = String.Concat(errorMessage, theException.Message);
errorMessage = String.Concat(errorMessage, " Line: ");
errorMessage = String.Concat(errorMessage, theException.Source);
MessageBox.Show(errorMessage, "Error");
}
}
System.Type ExcelType = System.Type.GetTypeFromProgID("Excel.Application");
Microsoft.Office.Interop.Excel.Application obj = Activator.CreateInstance(ExcelType) as Microsoft.Office.Interop.Excel.Application;