打开Excel的VBA帮助，查看Excel的对象模型，很容易找到完成这个功能需要的几个集合和对象：
Application、Workbooks、 Workbook、Worksheets还有Worksheet和Range。
Application创建Excel应用，Workbooks打开 Excel文档，Workbook获得Excel文档工作薄，Worksheets操作工作表集合，Worksheet获得单个工作表。
搜索的思路对应上述集合和对象，可以这样表述：要搜索的文本可能存在Excel文档当中的某个工作表上，搜索应该遍历目标Excel文件的每个工作表中的有效区域，如果找到，则退出本次搜索，如果没有找到，则继续搜索直到完成本次搜索。
跟Word对象模型不一样的是，Excel对象模型没有提供Find对象，不过没有关系，可以通过两种方法来实现，一个是通过Range对象的Find() 方法来实现; 另外一个比较麻烦，取得工作表Worksheet的有效区域UsedRange之后，遍历该Range对象中的所有行列。实际开发中，用第二 种方法时发现了一个特别的现象，所以第二种方法也准备详细记述一下。
1. 打开Excel文档：
object filename=""; object MissingValue=Type.Missing; string strKeyWord=""; //指定要搜索的文本，如果有多个，则声明string[] Excel.Application ep=new Excel.ApplicationClass(); Excel.Workbook ew=ep.Workbooks.Open(filename.ToString(),MissingValue, MissingValue,MissingValue,MissingValue, MissingValue,MissingValue,MissingValue, MissingValue,MissingValue,MissingValue, MissingValue,MissingValue,MissingValue, MissingValue);
2. 准备遍历Excel工作表
2.1 方法1
Excel.Worksheet ews;
int iEWSCnt=ew.Worksheets.Count;
int i=0,j=0;
Excel.Range oRange;
object oText=strKeyWord.Trim().ToUpper();
for(i=1;i<=iEWSCnt;i++)
{
ews=null;
ews=(Excel.Worksheet)ew.Worksheets[i];
oRange=null;
(Excel.Range)oRange=((Excel.Range)ews.UsedRange).Find(
oText,MissingValue,MissingValue,
MissingValue,MissingValue,Excel.XlSearchDirection.xlNext,
MissingValue,MissingValue,MissingValue);
if (oRange!=null && oRange.Cells.Rows.Count>=1 && oRange.Cells.Columns.Count>=1)
{
MessageBox.Show("文档中包含指定的关键字！","搜索结果",MessageBoxButtons.OK);
break;
}
}
这里要说两个值得注意的地方。一个是遍历工作表的索引，不是从0开始，而是从1开始；另外一个是Find方法的第六个参数 SearchDirection，指定搜索的方向，帮助文档中说这个参数是可选项，但是我用MissingValue如论如何编译不能通过，不知什么原 因，于是显式指定它的默认值xlNext。
2.2 方法2
第一种方法实现了，再看看第二种方法。这种方法除了要遍历工作表，还要对工作表使用区域的行和列进行遍历。其它一样，只对遍历说明，代码如下：
bool blFlag=false;
int iRowCnt=0,iColCnt=0,iBgnRow,iBgnCol;
for(m=1;m<=iEWSCnt;m++)
{
ews=(Excel.Worksheet)ew.Worksheets[m];
iRowCnt=0+ews.UsedRange.Cells.Rows.Count;
iColCnt=0+ews.UsedRange.Cells.Columns.Count;
iBgnRow=(ews.UsedRange.Cells.Row>1)? ews.UsedRange.Cells.Row-1:ews.UsedRange.Cells.Row;
iBgnCol=(ews.UsedRange.Cells.Column>1)? ews.UsedRange.Cells.Column-1:ews.UsedRange.Cells.Column;
for(i=iBgnRow;i
{
for(j=iBgnCol;j
{
strText=((Excel.Range)ews.UsedRange.Cells[i,j]).Text.ToString();
if (strText.ToUpper().IndexOf(strKeyWord.ToUpper())>=0)
{
MessageBox.Show("文档中包含指定的关键字！","搜索结果",MessageBoxButtons.OK);
}
}
}
}
显然这种方法比第一种繁琐得多，不过这里有一个关于遍历单元格的索引很特别的地方，当工作表中的使用区域UsedRange为单行单列的时候，对 UsedRange中的单元格遍历起始索引值为1，为多行多列的时候，起始索引值为0，不知这是Excel程序设计者出于什么样的考虑？
2.3 方法二补充案例
有效数据的行列数，可以通过下面的代码获取。
nUsedRow = sheet.UsedRange.Rows.Count;
nUsedCol = sheet.UsedRange.Columns.Count;
本文表示对参考文章1，文章2.2中原作者所说的那种奇怪的现象表示质疑，并不会出现那种情况。 2016-8-27
准备工作
private void createOutputFile(string excelFullFilename) { bool isAutoFit = true; bool isHeaderBold = true; Excel.Application xlApp = new Excel.Application(); Excel.Workbook xlWorkBook; Excel.Worksheet xlWorkSheet; object misValue = System.Reflection.Missing.Value; xlApp = new Excel.ApplicationClass(); xlWorkBook = xlApp.Workbooks.Add(misValue); xlWorkSheet = (Excel.Worksheet)xlWorkBook.Worksheets.get_Item(1); const int excelRowHeader = 1; const int excelColumnHeader = 1; //save header int curColumnIdx = 0 + excelColumnHeader; int rowIdx = 0 + excelRowHeader; xlWorkSheet.Cells[rowIdx, curColumnIdx++] = "Title"; xlWorkSheet.Cells[rowIdx, curColumnIdx++] = "Description"; const int constBullerLen = 5; for (int bulletIdx = 0; bulletIdx < constBullerLen; bulletIdx++) { int bulletNum = bulletIdx + 1; xlWorkSheet.Cells[rowIdx, curColumnIdx + bulletIdx] = "Bullet" + bulletNum.ToString(); } curColumnIdx = curColumnIdx + constBullerLen; const int constImgNameListLen = 5; for (int imgIdx = 0; imgIdx < constImgNameListLen; imgIdx++) { int imgNum = imgIdx + 1; xlWorkSheet.Cells[rowIdx, curColumnIdx + imgIdx] = "ImageFilename" + imgNum.ToString(); } curColumnIdx = curColumnIdx + constImgNameListLen; xlWorkSheet.Cells[rowIdx, curColumnIdx++] = "HighestPrice"; xlWorkSheet.Cells[rowIdx, curColumnIdx++] = "OneSellerIsAmazon"; xlWorkSheet.Cells[rowIdx, curColumnIdx++] = "ReviewNumber"; xlWorkSheet.Cells[rowIdx, curColumnIdx++] = "IsBestSeller"; //formatting //(1) header to bold if (isHeaderBold) { Range headerRow = xlWorkSheet.get_Range("1:1", System.Type.Missing); headerRow.Font.Bold = true; } //(2) auto adjust column width (according to content) if (isAutoFit) { Range allColumn = xlWorkSheet.Columns; allColumn.AutoFit(); } //output xlWorkBook.SaveAs(excelFullFilename, XlFileFormat.xlWorkbookNormal, misValue, misValue, misValue, misValue, XlSaveAsAccessMode.xlExclusive, XlSaveConflictResolution.xlLocalSessionChanges, misValue, misValue, misValue, misValue); xlWorkBook.Close(true, misValue, misValue); xlApp.Quit(); crl.releaseObject(xlWorkSheet); crl.releaseObject(xlWorkBook); crl.releaseObject(xlApp); }
现在需要用C#去打开已经存在的一个excel，并且找到最后一行，然后按行，继续添加内容。
private void appendInfoToFile(string fullFilename, AmazonProductInfo productInfo) { Excel.Application xlApp; Excel.Workbook xlWorkBook; Excel.Worksheet xlWorkSheet; object missingVal = System.Reflection.Missing.Value; xlApp = new Microsoft.Office.Interop.Excel.Application(); //xlApp.Visible = true; //xlApp.DisplayAlerts = false; //http://msdn.microsoft.com/zh-cn/library/microsoft.office.interop.excel.workbooks.open%28v=office.11%29.aspx xlWorkBook = xlApp.Workbooks.Open( Filename : fullFilename, //UpdateLinks:3, ReadOnly : false, //Format : 2, //use Commas as delimiter when open text file //Password : missingVal, //WriteResPassword : missingVal, //IgnoreReadOnlyRecommended: false, //when save to readonly, will notice you Origin: Excel.XlPlatform.xlWindows, //xlMacintosh/xlWindows/xlMSDOS //Delimiter: ",", // usefule when is text file Editable : true, Notify : false, //Converter: missingVal, AddToMru: true, //True to add this workbook to the list of recently used files Local: true, CorruptLoad: missingVal //xlNormalLoad/xlRepairFile/xlExtractData ); //Get the first sheet xlWorkSheet = (Excel.Worksheet)xlWorkBook.Worksheets.get_Item(1); //also can get by sheet name Excel.Range range = xlWorkSheet.UsedRange; //int usedColCount = range.Columns.Count; int usedRowCount = range.Rows.Count; const int excelRowHeader = 1; const int excelColumnHeader = 1; //int curColumnIdx = usedColCount + excelColumnHeader; int curColumnIdx = 0 + excelColumnHeader; //start from column begin int curRrowIdx = usedRowCount + excelRowHeader; // !!! here must added buildin excelRowHeader=1, otherwise will overwrite previous (added title or whole row value) xlWorkSheet.Cells[curRrowIdx, curColumnIdx++] = productInfo.title; xlWorkSheet.Cells[curRrowIdx, curColumnIdx++] = productInfo.description; const int constBullerLen = 5; int bulletListLen = 0; if (productInfo.bulletArr.Length > constBullerLen) { bulletListLen = constBullerLen; } else { bulletListLen = productInfo.bulletArr.Length; } for (int bulletIdx = 0; bulletIdx < bulletListLen; bulletIdx++) { xlWorkSheet.Cells[curRrowIdx, curColumnIdx + bulletIdx] = productInfo.bulletArr[bulletIdx]; } curColumnIdx = curColumnIdx + bulletListLen; const int constImgNameListLen = 5; int imgNameListLen = 0; if (productInfo.imgFullnameArr.Length > constImgNameListLen) { imgNameListLen = constImgNameListLen; } else { imgNameListLen = productInfo.imgFullnameArr.Length; } for (int imgIdx = 0; imgIdx < imgNameListLen; imgIdx++) { xlWorkSheet.Cells[curRrowIdx, curColumnIdx + imgIdx] = productInfo.imgFullnameArr[imgIdx]; } curColumnIdx = curColumnIdx + imgNameListLen; xlWorkSheet.Cells[curRrowIdx, curColumnIdx++] = productInfo.highestPrice; xlWorkSheet.Cells[curRrowIdx, curColumnIdx++] = productInfo.isOneSellerIsAmazon; xlWorkSheet.Cells[curRrowIdx, curColumnIdx++] = productInfo.reviewNumber; xlWorkSheet.Cells[curRrowIdx, curColumnIdx++] = productInfo.isBestSeller; ////http://msdn.microsoft.com/query/dev10.query?appId=Dev10IDEF1&l=ZH-CN&k=k%28MICROSOFT.OFFICE.INTEROP.EXCEL._WORKBOOK.SAVEAS%29;k%28SAVEAS%29;k%28TargetFrameworkMoniker-%22.NETFRAMEWORK%2cVERSION%3dV3.5%22%29;k%28DevLang-CSHARP%29&rd=true //xlWorkBook.SaveAs( // Filename: fullFilename, // ConflictResolution: XlSaveConflictResolution.xlLocalSessionChanges //The local user's changes are always accepted. // //FileFormat : Excel.XlFileFormat.xlWorkbookNormal //); //if use above SaveAs -> will popup a window ask you overwrite it or not, even if you have set the ConflictResolution to xlLocalSessionChanges, which should not ask, should directly save xlWorkBook.Save(); //http://msdn.microsoft.com/query/dev10.query?appId=Dev10IDEF1&l=ZH-CN&k=k%28MICROSOFT.OFFICE.INTEROP.EXCEL._WORKBOOK.CLOSE%29;k%28CLOSE%29;k%28TargetFrameworkMoniker-%22.NETFRAMEWORK%2cVERSION%3dV3.5%22%29;k%28DevLang-CSHARP%29&rd=true xlWorkBook.Close(SaveChanges : true); crl.releaseObject(xlWorkSheet); crl.releaseObject(xlWorkBook); crl.releaseObject(xlApp); }
参考文章
1.C#编程实现Excel文档中搜索文本内容的方法及思路 ，2013-7
2.How to append existing excel file using C# ?
3.MSDN, Workbooks.Open Method