两招搞定C#读取Excel文件

转载于：http://developer.51cto.com/art/200908/142392.htm

C#读取Excel文件可以通过直接读取和OleDb连接，把excel文件作为数据源来读取；本文结合具体代码向您介绍C#读取Excel文件的方法。

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C#读取Excel文件方法一：直接读取（这种直接读取单元格的方法释放很重要）

Excel.Applicationexcel=null;  
Excel.Workbookswbs=null;  
Excel.Workbookwb=null;  
Excel.Worksheetws=null;  
Excel.Rangerange1=null;  
objectNothing=System.Reflection.Missing.Value;  

try  
{  
excel=new Excel.Application();  
excel.UserControl=true;  
excel.DisplayAlerts=false;  

excel.Application.Workbooks.Open(this.FilePath,Nothing,Nothing,Nothing,Nothing,Nothing,Nothing,Nothing,Nothing,Nothing,Nothing,Nothing,Nothing);  

wbs=excel.Workbooks;  
wb=wbs[1];  
ws=(Excel.Worksheet)wb.Worksheets["Sheet2"];  


introwCount=ws.UsedRange.Rows.Count;  
intcolCount=ws.UsedRange.Columns.Count;  
if(rowCount<=0)  
throw new InvalidFormatException("文件中没有数据记录");  
if(colCount<4)  
throw new InvalidFormatException("字段个数不对");  

//此处有些问题 for(int i=0;i{this.rowNo=i+1;object[]row=newobject[4];  
for(int j=0;j<4;j++)  
{  
range1=ws.get_Range(ws.Cells[i+2,j+1],  
ws.Cells[i+2,j+1]);  
row[j]=range1.Value;  

if(row[0]==null)  
{  
this.isNullRecord++;  
break;  
}  
}  

if(this.isNullRecord>0)  
continue;  

DataRowdataRow=this.readExcel(row);  

if(this.isNullRecord==1)  
continue;  

if(this.verifyData(dataRow)==false)  
errFlag++;  

this.updateTableCurr(dataRow);  
}  
}  
finally  
{  
if(excel!=null)  
{  
if(wbs!=null)  
{  
if(wb!=null)  
{  
if(ws!=null)  
{  
if(range1!=null)  
{  
System.Runtime.InteropServices.Marshal.  
ReleaseComObject(range1);  
range1=null;  
}  
System.Runtime.InteropServices.Marshal.  
ReleaseComObject(ws);  
ws=null;  
}  
wb.Close(false,Nothing,Nothing);  
System.Runtime.InteropServices.Marshal.  
ReleaseComObject(wb);  
wb=null;  
}  
wbs.Close();  
System.Runtime.InteropServices.Marshal.  
ReleaseComObject(wbs);  
wbs=null;  
}  
excel.Application.Workbooks.Close();  
excel.Quit();  
System.Runtime.InteropServices.Marshal.  
ReleaseComObject(excel);  
excel=null;  
GC.Collect();  
}  
}

C#读取Excel文件方法二：通过OleDb连接，把excel文件作为数据源来读取（这里是fill进dataset，也可以返回OleDbDataReader来逐行读，数据较快）

注：这种方法容易把混合型的字段作为null值读取进来，解决办法是改造连接字符串

strConn = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\\Erp1912.xls;Extended Properties='Excel8.0;HDR=Yes;IMEX=1'";

通过Imex=1来把混合型作为文本型读取，避免null值,来实现C#读取Excel文件

private DataSet importExcelToDataSet(string FilePath)  
{  
   string strConn;  
   strConn="Provider=Microsoft.Jet.OLEDB.4.0;"+"DataSource="+FilePath+";Extended Properties=Excel8.0;";  
   OlebConnection conn=new OleDbConnection(strConn);  
   OleDbDataAdapter myCommand=new OleDbDataAdapter("SELECT*FROM[Sheet1$]",strConn);  
   DataSetmyDataSet=newDataSet();  
   try  
   {  
     myCommand.Fill(myDataSet);  
   }  
   catch(Exceptionex)  
   {  
      throw new InvalidFormatException("该Excel文件的工作表的名字不正确,"+ex.Message);  
   }  
   returnmyDataSet;  
}