如何使用.NET操作Excel组件NPOI?

如何使用.NET操作Excel组件NPOI?

很多的软件项目几乎都包含着对文档的操作,前面已经介绍过两款操作文档的组件,现在介绍一款文档操作的组件NPOI。

NPOI可以生成没有安装在您的服务器上的Microsoft Office套件的Excel报表,并且在后台调用Microsoft Excel ActiveX更有效率;从Office文档中提取文本,以帮助您实现全文索引功能(大多数时候,此功能用于创建搜索引擎); 从Office文档提取图像; 生成包含公式的Excel工作表。

一.NPOI组件概述:

NPOI是完全免费使用; 涵盖Excel的大多数功能(单元格样式,数据格式,公式等);支持xls,xlsx,docx;设计为面向接口(看看NPOI.SS命名空间);支持不仅导出而且导入; .Net 2.0甚至为xlsx和docx(虽然我们也支持.NET 4.0); 来自世界各地的成功案例;巨大的基本例子;对隔离存储没有依赖。

以上是NPOI的优点,其他一些优点可以不用太在意,估计很多人对“支持xls,xlsx,docx”这一特点感觉有些惊讶,因为在很多人的印象里面NPOI就是对Excel进行相关的操作,但是在这里突然看到了对docx也可以操作,这一特点可能让很多人感到欣喜,因为NPOI的的确确是一个很不错的组件,用过的人都说好,我也不例外。

NPOI的运行要求:VS2010与.NET 4.0运行时;VS2005或VS2008与.NET 2.0运行时(SP1);vs2003与.NET 1.1;Mono;ASP.NET中的中等信任环境。

二.NPOI核心类和方法解析:

以上是对NPOI的相关背景和使用环境做了一个简单的介绍,接下来我具体的看一下NPOI的一些核心类和方法,由于下载的是DLL文件,还是采用.NET Reflector对DLL文件进行反编译,以此查看源代码。

如果需要具体的了解NPOI可以直接访问:http://npoi.codeplex.com/SourceControl/latest,提供了NPOI的源码和一些demo,由于本溪介绍的重点是NPOI对Excel的操作,所以下面的类和实例主要是对操作Excel的介绍,如果需要对docx的操作,可以具体查看相应的类demo。

如何使用.NET操作Excel组件NPOI?

1.XSSFWorkbook类CreateSheet():创建表。

public ISheet CreateSheet(string sheetname)
{
 if (sheetname == null)
 {
  throw new ArgumentException("sheetName must not be null");
 }
 if (this.ContainsSheet(sheetname, this.sheets.Count))
 {
  throw new ArgumentException("The workbook already contains a sheet of this name");
 }
 if (sheetname.Length > 0x1f)
 {
  sheetname = sheetname.Substring(0, 0x1f);
 }
 WorkbookUtil.ValidateSheetName(sheetname);
 CT_Sheet sheet = this.AddSheet(sheetname);
 int index = 1;
 foreach (XSSFSheet sheet2 in this.sheets)
 {
  index = (int) Math.Max((long) (sheet2.sheet.sheetId + 1), (long) index);
 }
Label_0099:
 foreach (XSSFSheet sheet3 in this.sheets)
 {
  index = (int) Math.Max((long) (sheet3.sheet.sheetId + 1), (long) index);
 }
 string fileName = XSSFRelation.WORKSHEET.GetFileName(index);
 foreach (POIXMLDocumentPart part in base.GetRelations())
 {
  if ((part.GetPackagePart() != null) && fileName.Equals(part.GetPackagePart().PartName.Name))
  {
   index++;
   goto Label_0099;
  }
 }
 XSSFSheet item = (XSSFSheet) base.CreateRelationship(XSSFRelation.WORKSHEET, XSSFFactory.GetInstance(), index);
 item.sheet = sheet;
 sheet.id = item.GetPackageRelationship().Id;
 sheet.sheetId = (uint) index;
 if (this.sheets.Count == 0)
 {
  item.IsSelected = true;
 }
 this.sheets.Add(item);
 return item;
}

2.XSSFSheet类Write():将文件流写入到excel。

 internal virtual void Write(Stream stream)
{
 bool flag = false;
 if (this.worksheet.sizeOfColsArray() == 1)
 {
  CT_Cols colsArray = this.worksheet.GetColsArray(0);
  if (colsArray.sizeOfColArray() == 0)
  {
   flag = true;
   this.worksheet.SetColsArray(null);
  }
  else
  {
   this.SetColWidthAttribute(colsArray);
  }
 }
 if (this.hyperlinks.Count > 0)
 {
  if (this.worksheet.hyperlinks == null)
  {
   this.worksheet.AddNewHyperlinks();
  }
  CT_Hyperlink[] array = new CT_Hyperlink[this.hyperlinks.Count];
  for (int i = 0; i < array.Length; i++)
  {
   XSSFHyperlink hyperlink = this.hyperlinks[i];
   hyperlink.GenerateRelationIfNeeded(base.GetPackagePart());
   array[i] = hyperlink.GetCTHyperlink();
  }
  this.worksheet.hyperlinks.SetHyperlinkArray(array);
 }
 foreach (XSSFRow row in this._rows.Values)
 {
  row.OnDocumentWrite();
 }
 Dictionary<string, string> dictionary = new Dictionary<string, string>();
 dictionary[ST_RelationshipId.NamespaceURI] = "r";
 new WorksheetDocument(this.worksheet).Save(stream);
 if (flag)
 {
  this.worksheet.AddNewCols();
 }
}

3.XSSFSheet类CreateRow():创建行。

 public virtual IRow CreateRow(int rownum)
{
 CT_Row cTRow;
 XSSFRow row2 = this._rows.ContainsKey(rownum) ? this._rows[rownum] : null;
 if (row2 != null)
 {
  cTRow = row2.GetCTRow();
  cTRow.Set(new CT_Row());
 }
 else if ((this._rows.Count == 0) || (rownum > this.GetLastKey(this._rows.Keys)))
 {
  cTRow = this.worksheet.sheetData.AddNewRow();
 }
 else
 {
  int count = this.HeadMap(this._rows, rownum).Count;
  cTRow = this.worksheet.sheetData.InsertNewRow(count);
 }
 XSSFRow row3 = new XSSFRow(cTRow, this) {
  RowNum = rownum
 };
 this._rows[rownum] = row3;
 return row3;
}

4.XSSFWorkbook类GetSheet:获取表。

 public ISheet GetSheet(string name)
{
 foreach (XSSFSheet sheet in this.sheets)
 {
  if (name.Equals(sheet.SheetName, StringComparison.InvariantCultureIgnoreCase))
  {
   return sheet;
  }
 }
 return null;
}

5.WorkbookFactory类:

 public class PropertySetFactory
 {
 public static PropertySet Create(DirectoryEntry dir, string name);
 public static PropertySet Create(Stream stream);
 public static SummaryInformation CreateSummaryInformation();
 public static DocumentSummaryInformation CreateDocumentSummaryInformation();
 }

6.DocumentSummaryInformation:

 [Serializable]
public class DocumentSummaryInformation : SpecialPropertySet
{
 // Fields
 public const string DEFAULT_STREAM_NAME = "\x0005DocumentSummaryInformation";

 // Methods
 public DocumentSummaryInformation(PropertySet ps);
 private void EnsureSection2();
 public void RemoveByteCount();
 public void RemoveCategory();
 public void RemoveCompany();
 public void RemoveCustomProperties();
 public void RemoveDocparts();
 public void RemoveHeadingPair();
 public void RemoveHiddenCount();
 public void RemoveLineCount();
 public void RemoveLinksDirty();
 public void RemoveManager();
 public void RemoveMMClipCount();
 public void RemoveNoteCount();
 public void RemoveParCount();
 public void RemovePresentationFormat();
 public void RemoveScale();
 public void RemoveSlideCount();

 // Properties
 public int ByteCount { get; set; }
 public string Category { get; set; }
 public string Company { get; set; }
 public CustomProperties CustomProperties { get; set; }
 public byte[] Docparts { get; set; }
 public byte[] HeadingPair { get; set; }
 public int HiddenCount { get; set; }
 public int LineCount { get; set; }
 public bool LinksDirty { get; set; }
 public string Manager { get; set; }
 public int MMClipCount { get; set; }
 public int NoteCount { get; set; }
 public int ParCount { get; set; }
 public string PresentationFormat { get; set; }
 public override PropertyIDMap PropertySetIDMap { get; }
 public bool Scale { get; set; }
 public int SlideCount { get; set; }
}

具体方法:

private void EnsureSection2()
{
 if (this.SectionCount < 2)
 {
  MutableSection section = new MutableSection();
  section.SetFormatID(SectionIDMap.DOCUMENT_SUMMARY_INFORMATION_ID2);
  this.AddSection(section);
 }
}

以上只是对部分的类和方法做了简单的说明,需要了解更多的内容,可以进入官网下载源码,或者使用软件查看DLL文件。

三.NPOI操作实例:

1.枚举(Excel单元格数据类型):

 /// <summary>
 /// 枚举(Excel单元格数据类型)
 /// </summary>
 public enum NpoiDataType
 {
  /// <summary>
  /// 字符串类型-值为1
  /// </summary>
  String,
  /// <summary>
  /// 布尔类型-值为2
  /// </summary>
  Bool,
  /// <summary>
  /// 时间类型-值为3
  /// </summary>
  Datetime,
  /// <summary>
  /// 数字类型-值为4
  /// </summary>
  Numeric,
  /// <summary>
  /// 复杂文本类型-值为5
  /// </summary>
  Richtext,
  /// <summary>
  /// 空白
  /// </summary>
  Blank,
  /// <summary>
  /// 错误
  /// </summary>
  Error
 }

2. 将DataTable数据导入到excel中:

 /// <summary>
  /// 将DataTable数据导入到excel中
  /// </summary>
  /// <param name="data">要导入的数据</param>
  /// <param name="isColumnWritten">DataTable的列名是否要导入</param>
  /// <param name="sheetName">要导入的excel的sheet的名称</param>
  /// <param name="fileName">文件夹路径</param>
  /// <returns>导入数据行数(包含列名那一行)</returns>
  public static int DataTableToExcel(DataTable data, string sheetName, bool isColumnWritten, string fileName)
  {
   if (data == null)
   {
    throw new ArgumentNullException("data");
   }
   if (string.IsNullOrEmpty(sheetName))
   {
    throw new ArgumentNullException(sheetName);
   }
   if (string.IsNullOrEmpty(fileName))
   {
    throw new ArgumentNullException(fileName);
   }
   IWorkbook workbook = null;
   if (fileName.IndexOf(".xlsx", StringComparison.Ordinal) > 0)
   {
    workbook = new XSSFWorkbook();
   }    
   else if (fileName.IndexOf(".xls", StringComparison.Ordinal) > 0)
   {
    workbook = new HSSFWorkbook();
   }

   FileStream fs = null;
   try
   {
    fs = new FileStream(fileName, FileMode.OpenOrCreate, FileAccess.ReadWrite);
    ISheet sheet;
    if (workbook != null)
    {
     sheet = workbook.CreateSheet(sheetName);
    }
    else
    {
     return -1;
    }

    int j;
    int count;
    //写入DataTable的列名,写入单元格中
    if (isColumnWritten)
    {
     var row = sheet.CreateRow(0);
     for (j = 0; j < data.Columns.Count; ++j)
     {
      row.CreateCell(j).SetCellValue(data.Columns[j].ColumnName);
     }
     count = 1;
    }
    else
    {
     count = 0;
    }
    //遍历循环datatable具体数据项
    int i;
    for (i = 0; i < data.Rows.Count; ++i)
    {
     var row = sheet.CreateRow(count);
     for (j = 0; j < data.Columns.Count; ++j)
     {
      row.CreateCell(j).SetCellValue(data.Rows[i][j].ToString());
     }
     ++count;
    }
    //将文件流写入到excel
    workbook.Write(fs);
    return count;
   }
   catch (IOException ioex)
   {
    throw new IOException(ioex.Message);
   }
   catch (Exception ex)
   {
    throw new Exception(ex.Message);
   }
   finally
   {
    if (fs != null)
    {
     fs.Close();
    }
   }
  }

3.将excel中的数据导入到DataTable中:

 /// <summary>
  /// 将excel中的数据导入到DataTable中
  /// </summary>
  /// <param name="sheetName">excel工作薄sheet的名称</param>
  /// <param name="isFirstRowColumn">第一行是否是DataTable的列名</param>
  /// <param name="fileName">文件路径</param>
  /// <returns>返回的DataTable</returns>
  public static DataTable ExcelToDataTable(string sheetName, bool isFirstRowColumn, string fileName)
  {
   if (string.IsNullOrEmpty(sheetName))
   {
    throw new ArgumentNullException(sheetName);
   }
   if (string.IsNullOrEmpty(fileName))
   {
    throw new ArgumentNullException(fileName);
   }
   var data = new DataTable();
   IWorkbook workbook = null;
   FileStream fs = null;
   try
   {
    fs = new FileStream(fileName, FileMode.Open, FileAccess.Read);
    if (fileName.IndexOf(".xlsx", StringComparison.Ordinal) > 0)
    {
     workbook = new XSSFWorkbook(fs);
    }
    else if (fileName.IndexOf(".xls", StringComparison.Ordinal) > 0)
    {
     workbook = new HSSFWorkbook(fs);
    }

    ISheet sheet = null;
    if (workbook != null)
    {
     //如果没有找到指定的sheetName对应的sheet,则尝试获取第一个sheet
     sheet = workbook.GetSheet(sheetName) ?? workbook.GetSheetAt(0);
    }
    if (sheet == null) return data;
    var firstRow = sheet.GetRow(0);
    //一行最后一个cell的编号 即总的列数
    int cellCount = firstRow.LastCellNum;
    int startRow;
    if (isFirstRowColumn)
    {
     for (int i = firstRow.FirstCellNum; i < cellCount; ++i)
     {
      var cell = firstRow.GetCell(i);
      var cellValue = cell.StringCellValue;
      if (cellValue == null) continue;
      var column = new DataColumn(cellValue);
      data.Columns.Add(column);
     }
     startRow = sheet.FirstRowNum + 1;
    }
    else
    {
     startRow = sheet.FirstRowNum;
    }
    //最后一列的标号
    var rowCount = sheet.LastRowNum;
    for (var i = startRow; i <= rowCount; ++i)
    {
     var row = sheet.GetRow(i);
     //没有数据的行默认是null
     if (row == null) continue;
     var dataRow = data.NewRow();
     for (int j = row.FirstCellNum; j < cellCount; ++j)
     {
      //同理,没有数据的单元格都默认是null
      if (row.GetCell(j) != null)
       dataRow[j] = row.GetCell(j).ToString();
     }
     data.Rows.Add(dataRow);
    }

    return data;
   }
   catch (IOException ioex)
   {
    throw new IOException(ioex.Message);
   }
   catch (Exception ex)
   {
    throw new Exception(ex.Message);
   }
   finally
   {
    if (fs != null)
    {
     fs.Close();
    }
   }
  }

4.读取Excel文件内容转换为DataSet:

 /// <summary>
  /// 读取Excel文件内容转换为DataSet,列名依次为 "c0"……c[columnlength-1]
  /// </summary>
  /// <param name="fileName">文件绝对路径</param>
  /// <param name="startRow">数据开始行数(1为第一行)</param>
  /// <param name="columnDataType">每列的数据类型</param>
  /// <returns></returns>
  public static DataSet ReadExcel(string fileName, int startRow, params NpoiDataType[] columnDataType)
  {
   var ds = new DataSet("ds");
   var dt = new DataTable("dt");
   var sb = new StringBuilder();
   using (var stream = new FileStream(fileName, FileMode.Open, FileAccess.Read))
   {
    //使用接口,自动识别excel2003/2007格式
    var workbook = WorkbookFactory.Create(stream);
    //得到里面第一个sheet
    var sheet = workbook.GetSheetAt(0);
    int j;
    IRow row;
    //ColumnDataType赋值
    if (columnDataType.Length <= 0)
    {
     //得到第i行
     row = sheet.GetRow(startRow - 1);
     columnDataType = new NpoiDataType[row.LastCellNum];
     for (var i = 0; i < row.LastCellNum; i++)
     {
      var hs = row.GetCell(i);
      columnDataType[i] = GetCellDataType(hs);
     }
    }
    for (j = 0; j < columnDataType.Length; j++)
    {
     var tp = GetDataTableType(columnDataType[j]);
     dt.Columns.Add("c" + j, tp);
    }
    for (var i = startRow - 1; i <= sheet.PhysicalNumberOfRows; i++)
    {
     //得到第i行
     row = sheet.GetRow(i);
     if (row == null) continue;
     try
     {
      var dr = dt.NewRow();

      for (j = 0; j < columnDataType.Length; j++)
      {
       dr["c" + j] = GetCellData(columnDataType[j], row, j);
      }
      dt.Rows.Add(dr);
     }
     catch (Exception er)
     {
      sb.Append(string.Format("第{0}行出错:{1}\r\n", i + 1, er.Message));
     }
    }
    ds.Tables.Add(dt);
   }
   if (ds.Tables[0].Rows.Count == 0 && sb.ToString() != "") throw new Exception(sb.ToString());
   return ds;
  }

5.从DataSet导出到2003:

 /// <summary>
  /// 从DataSet导出到MemoryStream流2003
  /// </summary>
  /// <param name="saveFileName">文件保存路径</param>
  /// <param name="sheetName">Excel文件中的Sheet名称</param>
  /// <param name="ds">存储数据的DataSet</param>
  /// <param name="startRow">从哪一行开始写入,从0开始</param>
  /// <param name="datatypes">DataSet中的各列对应的数据类型</param>
  public static bool CreateExcel2003(string saveFileName, string sheetName, DataSet ds, int startRow, params NpoiDataType[] datatypes)
  {
   try
   {
    if (startRow < 0) startRow = 0;
    var wb = new HSSFWorkbook();
    var dsi = PropertySetFactory.CreateDocumentSummaryInformation();
    dsi.Company = "pkm";
    var si = PropertySetFactory.CreateSummaryInformation();
    si.Title =
    si.Subject = "automatic genereted document";
    si.Author = "pkm";
    wb.DocumentSummaryInformation = dsi;
    wb.SummaryInformation = si;
    var sheet = wb.CreateSheet(sheetName);
    //sheet.SetColumnWidth(0, 50 * 256);
    //sheet.SetColumnWidth(1, 100 * 256);
    ICell cell;
    int j;
    var maxLength = 0;
    var curLength = 0;
    object columnValue;
    var dt = ds.Tables[0];
    if (datatypes.Length < dt.Columns.Count)
    {
     datatypes = new NpoiDataType[dt.Columns.Count];
     for (var i = 0; i < dt.Columns.Count; i++)
     {
      var dtcolumntype = dt.Columns[i].DataType.Name.ToLower();
      switch (dtcolumntype)
      {
       case "string":
        datatypes[i] = NpoiDataType.String;
        break;
       case "datetime":
        datatypes[i] = NpoiDataType.Datetime;
        break;
       case "boolean":
        datatypes[i] = NpoiDataType.Bool;
        break;
       case "double":
        datatypes[i] = NpoiDataType.Numeric;
        break;
       default:
        datatypes[i] = NpoiDataType.String;
        break;
      }
     }
    }

    // 创建表头
    var row = sheet.CreateRow(0);
    //样式
    var style1 = wb.CreateCellStyle();
    //字体
    var font1 = wb.CreateFont();
    //字体颜色
    font1.Color = HSSFColor.White.Index;
    //字体加粗样式
    font1.Boldweight = (short)FontBoldWeight.Bold;
    //style1.FillBackgroundColor = HSSFColor.WHITE.index;               
    style1.FillForegroundColor = HSSFColor.Green.Index;
    //GetXLColour(wb, LevelOneColor);// 设置图案色
    //GetXLColour(wb, LevelOneColor);// 设置背景色
    style1.FillPattern = FillPattern.SolidForeground;
    //样式里的字体设置具体的字体样式
    style1.SetFont(font1);
    //文字水平对齐方式
    style1.Alignment = HorizontalAlignment.Center;
    //文字垂直对齐方式
    style1.VerticalAlignment = VerticalAlignment.Center;
    row.HeightInPoints = 25;
    for (j = 0; j < dt.Columns.Count; j++)
    {
     columnValue = dt.Columns[j].ColumnName;
     curLength = Encoding.Default.GetByteCount(columnValue.ToString());
     maxLength = (maxLength < curLength ? curLength : maxLength);
     var colounwidth = 256 * maxLength;
     sheet.SetColumnWidth(j, colounwidth);
     try
     {
      //创建第0行的第j列
      cell = row.CreateCell(j);
      //单元格式设置样式
      cell.CellStyle = style1;

      try
      {
       cell.SetCellType(CellType.String);
       cell.SetCellValue(columnValue.ToString());
      }
      catch (Exception ex)
      {
       throw new Exception(ex.Message);
      }

     }
     catch (Exception ex)
     {
      throw new Exception(ex.Message);
     }
    }
    // 创建每一行
    for (var i = startRow; i < ds.Tables[0].Rows.Count; i++)
    {
     var dr = ds.Tables[0].Rows[i];
     //创建第i行
     row = sheet.CreateRow(i + 1);
     for (j = 0; j < dt.Columns.Count; j++)
     {
      columnValue = dr[j];
      curLength = Encoding.Default.GetByteCount(columnValue.ToString());
      maxLength = (maxLength < curLength ? curLength : maxLength);
      var colounwidth = 256 * maxLength;
      sheet.SetColumnWidth(j, colounwidth);
      try
      {
       //创建第i行的第j列
       cell = row.CreateCell(j);
       // 插入第j列的数据
       try
       {
        var dtype = datatypes[j];
        switch (dtype)
        {
         case NpoiDataType.String:
          {
           cell.SetCellType(CellType.Numeric);
           cell.SetCellValue(columnValue.ToString());
          }
          break;
         case NpoiDataType.Datetime:
          {
           cell.SetCellType(CellType.Numeric);
           cell.SetCellValue(columnValue.ToString());
          }
          break;
         case NpoiDataType.Numeric:
          {
           cell.SetCellType(CellType.Numeric);
           cell.SetCellValue(Convert.ToDouble(columnValue));
          }
          break;
         case NpoiDataType.Bool:
          {
           cell.SetCellType(CellType.Numeric);
           cell.SetCellValue(Convert.ToBoolean(columnValue));
          }
          break;
         case NpoiDataType.Richtext:
          {
           cell.SetCellType(CellType.Numeric);
           cell.SetCellValue(columnValue.ToString());
          }
          break;
        }
       }
       catch (Exception ex)
       {
        cell.SetCellType(CellType.Numeric);
        cell.SetCellValue(columnValue.ToString());
        throw new Exception(ex.Message);
       }
      }
      catch (Exception ex)
      {
       throw new Exception(ex.Message);
      }
     }
    }
    //生成文件在服务器上
    using (var fs = new FileStream(saveFileName, FileMode.OpenOrCreate, FileAccess.Write))
    {
     wb.Write(fs);
    }

    return true;
   }
   catch (Exception er)
   {
    throw new Exception(er.Message);
   }

  }

6.从DataSet导出到MemoryStream流2007:

/// <summary>
  /// 从DataSet导出到MemoryStream流2007
  /// </summary>
  /// <param name="saveFileName">文件保存路径</param>
  /// <param name="sheetName">Excel文件中的Sheet名称</param>
  /// <param name="ds">存储数据的DataSet</param>
  /// <param name="startRow">从哪一行开始写入,从0开始</param>
  /// <param name="datatypes">DataSet中的各列对应的数据类型</param>
  public static bool CreateExcel2007(string saveFileName, string sheetName, DataSet ds, int startRow, params NpoiDataType[] datatypes)
  {
   try
   {
    if (startRow < 0) startRow = 0;
    var wb = new XSSFWorkbook();
    var sheet = wb.CreateSheet(sheetName);
    ICell cell;
    int j;
    var maxLength = 0;
    int curLength;
    object columnValue;
    var dt = ds.Tables[0];
    if (datatypes.Length < dt.Columns.Count)
    {
     datatypes = new NpoiDataType[dt.Columns.Count];
     for (var i = 0; i < dt.Columns.Count; i++)
     {
      var dtcolumntype = dt.Columns[i].DataType.Name.ToLower();
      switch (dtcolumntype)
      {
       case "string":
        datatypes[i] = NpoiDataType.String;
        break;
       case "datetime":
        datatypes[i] = NpoiDataType.Datetime;
        break;
       case "boolean":
        datatypes[i] = NpoiDataType.Bool;
        break;
       case "double":
        datatypes[i] = NpoiDataType.Numeric;
        break;
       default:
        datatypes[i] = NpoiDataType.String;
        break;
      }
     }
    }
    //创建表头
    var row = sheet.CreateRow(0);
    //样式
    var style1 = wb.CreateCellStyle();
    //字体
    var font1 = wb.CreateFont();
    //字体颜色
    font1.Color = HSSFColor.White.Index;
    //字体加粗样式
    font1.Boldweight = (short)FontBoldWeight.Bold;
    //style1.FillBackgroundColor = HSSFColor.WHITE.index;
    //GetXLColour(wb, LevelOneColor);
    // 设置图案色
    style1.FillForegroundColor = HSSFColor.Green.Index;
    //GetXLColour(wb, LevelOneColor);// 设置背景色
    style1.FillPattern = FillPattern.SolidForeground;
    //样式里的字体设置具体的字体样式
    style1.SetFont(font1);
    //文字水平对齐方式
    style1.Alignment = HorizontalAlignment.Center;
    //文字垂直对齐方式
    style1.VerticalAlignment = VerticalAlignment.Center;
    row.HeightInPoints = 25;
    for (j = 0; j < dt.Columns.Count; j++)
    {
     columnValue = dt.Columns[j].ColumnName;
     curLength = Encoding.Default.GetByteCount(columnValue.ToString());
     maxLength = (maxLength < curLength ? curLength : maxLength);
     var colounwidth = 256 * maxLength;
     sheet.SetColumnWidth(j, colounwidth);
     try
     {
      //创建第0行的第j列
      cell = row.CreateCell(j);
      //单元格式设置样式
      cell.CellStyle = style1;

      try
      {
       cell.SetCellValue(columnValue.ToString());
      }
      catch (Exception ex)
      {
       throw new Exception(ex.Message);
      }

     }
     catch (Exception ex)
     {
      throw new Exception(ex.Message);
     }
    }
    // 创建每一行
    for (var i = startRow; i < ds.Tables[0].Rows.Count; i++)
    {
     var dr = ds.Tables[0].Rows[i];
     //创建第i行
     row = sheet.CreateRow(i + 1);
     for (j = 0; j < dt.Columns.Count; j++)
     {
      columnValue = dr[j];
      curLength = Encoding.Default.GetByteCount(columnValue.ToString());
      maxLength = (maxLength < curLength ? curLength : maxLength);
      var colounwidth = 256 * maxLength;
      sheet.SetColumnWidth(j, colounwidth);
      try
      {
       //创建第i行的第j列
       cell = row.CreateCell(j);
       // 插入第j列的数据
       try
       {
        var dtype = datatypes[j];
        switch (dtype)
        {
         case NpoiDataType.String:
          {
           cell.SetCellValue(columnValue.ToString());
          }
          break;
         case NpoiDataType.Datetime:
          {
           cell.SetCellValue(columnValue.ToString());
          }
          break;
         case NpoiDataType.Numeric:
          {
           cell.SetCellValue(Convert.ToDouble(columnValue));
          }
          break;
         case NpoiDataType.Bool:
          {
           cell.SetCellValue(Convert.ToBoolean(columnValue));
          }
          break;
         case NpoiDataType.Richtext:
          {
           cell.SetCellValue(columnValue.ToString());
          }
          break;
        }
       }
       catch (Exception ex)
       {
        cell.SetCellValue(columnValue.ToString());
        throw new Exception(ex.Message);
       }
      }
      catch (Exception ex)
      {
       throw new Exception(ex.Message);
      }
     }
    }
    //生成文件在服务器上
    using (var fs = new FileStream(saveFileName, FileMode.OpenOrCreate, FileAccess.Write))
    {
     wb.Write(fs);
    }
    return true;
   }
   catch (Exception er)
   {
    throw new Exception(er.Message);
   }

  }

7.读Excel-根据NpoiDataType创建的DataTable列的数据类型:

 /// <summary>
  /// 读Excel-根据NpoiDataType创建的DataTable列的数据类型
  /// </summary>
  /// <param name="datatype"></param>
  /// <returns></returns>
  private static Type GetDataTableType(NpoiDataType datatype)
  {
   var tp = typeof(string);
   switch (datatype)
   {
    case NpoiDataType.Bool:
     tp = typeof(bool);
     break;
    case NpoiDataType.Datetime:
     tp = typeof(DateTime);
     break;
    case NpoiDataType.Numeric:
     tp = typeof(double);
     break;
    case NpoiDataType.Error:
     tp = typeof(string);
     break;
    case NpoiDataType.Blank:
     tp = typeof(string);
     break;
   }
   return tp;
  }


  /// <summary>
  /// 读Excel-得到不同数据类型单元格的数据
  /// </summary>
  /// <param name="datatype">数据类型</param>
  /// <param name="row">数据中的一行</param>
  /// <param name="column">哪列</param>
  /// <returns></returns>
  private static object GetCellData(NpoiDataType datatype, IRow row, int column)
  {
   switch (datatype)
   {
    case NpoiDataType.String:
     try
     {
      return row.GetCell(column).DateCellValue;
     }
     catch
     {
      try
      {
       return row.GetCell(column).StringCellValue;
      }
      catch
      {
       return row.GetCell(column).NumericCellValue;
      }
     }
    case NpoiDataType.Bool:
     try { return row.GetCell(column).BooleanCellValue; }
     catch { return row.GetCell(column).StringCellValue; }
    case NpoiDataType.Datetime:
     try { return row.GetCell(column).DateCellValue; }
     catch { return row.GetCell(column).StringCellValue; }
    case NpoiDataType.Numeric:
     try { return row.GetCell(column).NumericCellValue; }
     catch { return row.GetCell(column).StringCellValue; }
    case NpoiDataType.Richtext:
     try { return row.GetCell(column).RichStringCellValue; }
     catch { return row.GetCell(column).StringCellValue; }
    case NpoiDataType.Error:
     try { return row.GetCell(column).ErrorCellValue; }
     catch { return row.GetCell(column).StringCellValue; }
    case NpoiDataType.Blank:
     try { return row.GetCell(column).StringCellValue; }
     catch { return ""; }
    default: return "";
   }
  }

  /// <summary>
  /// 获取单元格数据类型
  /// </summary>
  /// <param name="hs">单元格对象</param>
  /// <returns></returns>
  private static NpoiDataType GetCellDataType(ICell hs)
  {
   NpoiDataType dtype;
   DateTime t1;
   var cellvalue = "";

   switch (hs.CellType)
   {
    case CellType.Blank:
     dtype = NpoiDataType.String;
     cellvalue = hs.StringCellValue;
     break;
    case CellType.Boolean:
     dtype = NpoiDataType.Bool;
     break;
    case CellType.Numeric:
     dtype = NpoiDataType.Numeric;
     cellvalue = hs.NumericCellValue.ToString(CultureInfo.InvariantCulture);
     break;
    case CellType.String:
     dtype = NpoiDataType.String;
     cellvalue = hs.StringCellValue;
     break;
    case CellType.Error:
     dtype = NpoiDataType.Error;
     break;
    default:
     dtype = NpoiDataType.Datetime;
     break;
   }
   if (cellvalue != "" && DateTime.TryParse(cellvalue, out t1)) dtype = NpoiDataType.Datetime;
   return dtype;
  }


四.总结:

本文是接着上五篇介绍.NET组件,目的只是在于总结一些组件的用法,将文章作为一个引子,各位读者可以根据文章的介绍更加深入的去了解相关组件。有些地方写的有误,还望多多包涵和指正,欢迎大家给我建议介绍一些你们在项目中经常使用的组件,可以跟大家做一个分享。