【转载】C# 读取Excel文件代码的几种片段收集

片段 1

using System.Data.OleDb;

...


static void Main()
{
Application.Run(new Form1());
}

private void Form1_Load(object sender, System.EventArgs e)
{
DataTable myT=ExcelToDataTable("D:/文件/新武昌站点资料.xls","sheet1");
String mystr=myT.Rows[0][0].ToString();
this.textBox1.Text=mystr;
}

public static DataTable ExcelToDataTable(string strExcelFileName, string strSheetName)
{
//源的定义
string strConn = "Provider=Microsoft.Jet.OLEDB.4.0;" + "Data Source=" + strExcelFileName + ";" + "Extended Properties='Excel 8.0;HDR=NO;IMEX=1';";

//Sql语句
//string strExcel = string.Format("select * from [{0}$]", strSheetName); 这是一种方法
string strExcel = "select * from   [sheet1$]";

//定义存放的数据表
DataSet ds = new DataSet();

//连接数据源
OleDbConnection conn = new OleDbConnection(strConn);

conn.Open();

//适配到数据源
OleDbDataAdapter adapter = new OleDbDataAdapter(strExcel, strConn);
adapter.Fill(ds, strSheetName);

conn.Close();

return ds.Tables[strSheetName];
}

很简单的代码，但是问题就出在连接字符串上面，后面一定要加上Extended Properties='Excel 8.0;HDR=NO;IMEX=1'，HDR和IMEX也一定要配合使用，哈哈,老实说,我也不知道为什么,这样配合的效果最好,这是我艰苦调试的结果.IMEX=1应该是将所有的列全部视为文本,我也有点忘记了.至于HDR本来只是说是否要出现一行标题头而已,但是结果却会导致某些字段值丢失,所以其实我至今也搞不明白为什么,很可能是驱动的问题...

片段 2

提供两种方法：一个是直接打开excel文件，然后逐行读取，速度较慢；还有一种方法是通过OleDb连接，把excel文件作为数据源来读取
方法一：这种直接读取单元格的方法释放很重要。

  

Excel.Application excel = null;
   Excel.Workbooks wbs = null;
   Excel.Workbook wb = null;
   Excel.Worksheet ws = null;
   Excel.Range range1 = null;
   object Nothing = 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"];
    
         
    int rowCount = ws.UsedRange.Rows.Count;
    int colCount = 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");
    
    for (int i = 0;i    {

     this.rowNo = i + 1;
     object[] row = new object[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;

     DataRow dataRow = 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();
    }
   }

方法二：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='Excel 8.0;HDR=Yes;IMEX=1'";
通过Imex=1来把混合型作为文本型读取，避免null值,详细请见http://www.connectionstrings.com

private DataSet importExcelToDataSet(string FilePath)
{
   string strConn;
   strConn = "Provider=Microsoft.Jet.OLEDB.4.0;" + "Data Source=" + FilePath + ";Extended Properties=Excel 8.0;";
   OleDbConnection conn = new OleDbConnection(strConn);
   OleDbDataAdapter myCommand = new OleDbDataAdapter("SELECT * FROM [Sheet1$]",strConn);
   DataSet myDataSet = new DataSet();
   try
   {
    myCommand.Fill(myDataSet);
   }
   catch(Exception ex)
   {
    throw new InvalidFormatException("该Excel文件的工作表的名字不正确," + ex.Message);
   }
   return myDataSet;
}

片段 3

用c#读取excel文件,写到datagridview控件中

用c#读取excel文件,写到datagridview控件中

string strconn = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\MyExcel.xls;Extended Properties=""Excel 8.0;HDR=Yes;IMEX=1''" " ;

            OleDbConnection conn = new OleDbConnection(strconn);

            conn.Open();

            if (bo == false)

            {

                comboBox1.Items.Clear();

                DataTable dt = conn.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, new object[] { null, null, null, "TABLE" });

                foreach (DataRow dr in dt.Rows)

                {

                    comboBox1.Items.Add((String)dr["TABLE_NAME"]);

                    //MessageBox.Show((String)dr["TABLE_NAME"]);

                }

                //comboBox1.Text = comboBox1.Items[0].ToString();

            }

            else

            {

                string sql = "select * from " + comboBox1.Text;

                OleDbDataAdapter aper = new OleDbDataAdapter(sql, conn);

                DataSet myset = new DataSet();

                aper.Fill(myset, comboBox1.Text);

                dataGridView1.DataSource = myset.Tables[comboBox1.Text];

            }

            conn.Close();

备注：

@"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\MyExcel.xls;Extended Properties=""Excel 8.0;HDR=Yes;IMEX=1"""

"HDR=Yes;" indicates that the first row contains columnnames, not data

"IMEX=1;" tells the driver to always read "intermixed" data columns as text

TIP! SQL syntax: "SELECT * FROM [sheet1$]" - i.e. worksheet name followed by a "$" and wrapped in "[" "]" brackets.

如果第一行是数据而不是标题的话, 应该写: "HDR=No;"

"IMEX=1;" tells the driver to always read "intermixed" data columns as text

片段 4

C#读取Excel文件数据    
相当简单,Excel就像数据库,每个Sheet就是一个Table. Microsoft.Jet.OLEDB驱动.
之后是DataReader循环,或DataSet处理都非常简单.

HTTP://BLOG.CSDN.NET/CRABO/
注意:数据类型的转换!!

#region set connection
   string strConn = @"Provider=Microsoft.Jet.OLEDB.4.0;Data Source= "+this.txtPath.Text+";Extended Properties=Excel 8.0;";
   myDataReader = null;
craboDbConnection = new OleDbConnection(strConn);
   OleDbCommand myOleDbCommand = new OleDbCommand("SELECT * FROM [Sheet1$]", myOleDbConnection);
   #endregion

   try
   {
    myOleDbConnection.Open();
    myDataReader = myOleDbCommand.ExecuteReader();
    while (myDataReader.Read())
    {
       this.txtSeq.Text=Convert.ToString(myDataReader.GetValue(0));//列1
       this.txtName.Text=Convert.ToString(myDataReader.GetValue(1));//列2
       this.txtPIN.Text=Convert.ToString(myDataReader.GetValue(2));//列3
    }
}
   #region Catch
   catch(System.Threading.ThreadAbortException e)
   {
    System.Threading.Thread.ResetAbort();
    this.lblResult.Text = "线程被中断..."+e.Message;
   }
   catch(Exception ex)
   {
    System.Windows.Forms.MessageBox.Show(ex.ToString());
   }
   finally
   {
    // Always call Close when done reading.
    if (myDataReader != null)
     myDataReader.Close();

    // Close the connection when done with it.
    if (craboDbConnection!=null && craboDbConnection.State == ConnectionState.Open)
     craboDbConnection.Close();

    if(webResponse!=null)
     webResponse.Close();
   }
   #endregion