很多的軟件項目幾乎都包含著對文檔的操作，前面已經介紹過兩款操作文檔的組件，現在介紹一款文檔操作的組件NPOI。
NPOI可以生成沒有安裝在您的服務器上的Microsoft Office套件的Excel報表，並且在後台調用Microsoft Excel ActiveX更有效率;從Office文檔中提取文本，以幫助您實現全文索引功能（大多數時候，此功能用於創建搜索引擎）； 從Office文檔提取圖像； 生成包含公式的Excel工作表。
一.NPOI組件概述：
NPOI是完全免費使用； 涵蓋Excel的大多數功能（單元格樣式，數據格式，公式等）；支持xls，xlsx，docx；設計為面向接口（看看NPOI.SS命名空間）；支持不僅導出而且導入； .Net 2.0甚至為xlsx和docx（雖然我們也支持.NET 4.0）； 來自世界各地的成功案例；巨大的基本例子；對隔離存儲沒有依賴。
以上是NPOI的優點，其他一些優點可以不用太在意，估計很多人對“支持xls，xlsx，docx”這一特點感覺有些驚訝，因為在很多人的印象裡面NPOI就是對Excel進行相關的操作，但是在這裡突然看到了對docx也可以操作，這一特點可能讓很多人感到欣喜，因為NPOI的的確確是一個很不錯的組件，用過的人都說好，我也不例外。
NPOI的運行要求：VS2010與.NET 4.0運行時；VS2005或VS2008與.NET 2.0運行時（SP1）；vs2003與.NET 1.1；Mono；ASP.NET中的中等信任環境。
二.NPOI核心類和方法解析：
以上是對NPOI的相關背景和使用環境做了一個簡單的介紹，接下來我具體的看一下NPOI的一些核心類和方法，由於下載的是DLL文件，還是采用.NET Reflector對DLL文件進行反編譯，以此查看源代碼。
如果需要具體的了解NPOI可以直接訪問：http://npoi.codeplex.com/SourceControl/latest，提供了NPOI的源碼和一些demo，由於本溪介紹的重點是NPOI對Excel的操作，所以下面的類和實例主要是對操作Excel的介紹，如果需要對docx的操作，可以具體查看相應的類demo。
1.XSSFWorkbook類CreateSheet():創建表。
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類Write():將文件流寫入到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類CreateRow()：創建行。
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類GetSheet：獲取表。
public ISheet GetSheet(string name)
{
foreach (XSSFSheet sheet in this.sheets)
{
if (name.Equals(sheet.SheetName, StringComparison.InvariantCultureIgnoreCase))
{
return sheet;
}
}
return null;
}
5.WorkbookFactory類：
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; }
}
具體方法：
private void EnsureSection2()
{
if (this.SectionCount < 2)
{
MutableSection section = new MutableSection();
section.SetFormatID(SectionIDMap.DOCUMENT_SUMMARY_INFORMATION_ID2);
this.AddSection(section);
}
}
以上只是對部分的類和方法做了簡單的說明，需要了解更多的內容，可以進入官網下載源碼，或者使用軟件查看DLL文件。
三.NPOI操作實例：
1.枚舉(Excel單元格數據類型)：
/// <summary>
/// 枚舉(Excel單元格數據類型)
/// </summary>
public enum NpoiDataType
{
/// <summary>
/// 字符串類型-值為1
/// </summary>
String,
/// <summary>
/// 布爾類型-值為2
/// </summary>
Bool,
/// <summary>
/// 時間類型-值為3
/// </summary>
Datetime,
/// <summary>
/// 數字類型-值為4
/// </summary>
Numeric,
/// <summary>
/// 復雜文本類型-值為5
/// </summary>
Richtext,
/// <summary>
/// 空白
/// </summary>
Blank,
/// <summary>
/// 錯誤
/// </summary>
Error
}
2. 將DataTable數據導入到excel中：
/// <summary>
/// 將DataTable數據導入到excel中
/// </summary>
/// <param name="data">要導入的數據</param>
/// <param name="isColumnWritten">DataTable的列名是否要導入</param>
/// <param name="sheetName">要導入的excel的sheet的名稱</param>
/// <param name="fileName">文件夾路徑</param>
/// <returns>導入數據行數(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;
//寫入DataTable的列名，寫入單元格中
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;
}
//遍歷循環datatable具體數據項
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;
}
//將文件流寫入到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.將excel中的數據導入到DataTable中：
/// <summary>
/// 將excel中的數據導入到DataTable中
/// </summary>
/// <param name="sheetName">excel工作薄sheet的名稱</param>
/// <param name="isFirstRowColumn">第一行是否是DataTable的列名</param>
/// <param name="fileName">文件路徑</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)
{
//如果沒有找到指定的sheetName對應的sheet，則嘗試獲取第一個sheet
sheet = workbook.GetSheet(sheetName) ?? workbook.GetSheetAt(0);
}
if (sheet == null) return data;
var firstRow = sheet.GetRow(0);
//一行最後一個cell的編號 即總的列數
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;
}
//最後一列的標號
var rowCount = sheet.LastRowNum;
for (var i = startRow; i <= rowCount; ++i)
{
var row = sheet.GetRow(i);
//沒有數據的行默認是null
if (row == null) continue;
var dataRow = data.NewRow();
for (int j = row.FirstCellNum; j < cellCount; ++j)
{
//同理，沒有數據的單元格都默認是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.讀取Excel文件內容轉換為DataSet：
/// <summary>
/// 讀取Excel文件內容轉換為DataSet,列名依次為 "c0"……c[columnlength-1]
/// </summary>
/// <param name="fileName">文件絕對路徑</param>
/// <param name="startRow">數據開始行數(1為第一行)</param>
/// <param name="columnDataType">每列的數據類型</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，自動識別excel2003/2007格式
var workbook = WorkbookFactory.Create(stream);
//得到裡面第一個sheet
var sheet = workbook.GetSheetAt(0);
int j;
IRow row;
//ColumnDataType賦值
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}行出錯：{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.從DataSet導出到2003：
/// <summary>
/// 從DataSet導出到MemoryStream流2003
/// </summary>
/// <param name="saveFileName">文件保存路徑</param>
/// <param name="sheetName">Excel文件中的Sheet名稱</param>
/// <param name="ds">存儲數據的DataSet</param>
/// <param name="startRow">從哪一行開始寫入，從0開始</param>
/// <param name="datatypes">DataSet中的各列對應的數據類型</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;
}
}
}
// 創建表頭
var row = sheet.CreateRow(0);
//樣式
var style1 = wb.CreateCellStyle();
//字體
var font1 = wb.CreateFont();
//字體顏色
font1.Color = HSSFColor.White.Index;
//字體加粗樣式
font1.Boldweight = (short)FontBoldWeight.Bold;
//style1.FillBackgroundColor = HSSFColor.WHITE.index;
style1.FillForegroundColor = HSSFColor.Green.Index;
//GetXLColour(wb, LevelOneColor);// 設置圖案色
//GetXLColour(wb, LevelOneColor);// 設置背景色
style1.FillPattern = FillPattern.SolidForeground;
//樣式裡的字體設置具體的字體樣式
style1.SetFont(font1);
//文字水平對齊方式
style1.Alignment = HorizontalAlignment.Center;
//文字垂直對齊方式
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
{
//創建第0行的第j列
cell = row.CreateCell(j);
//單元格式設置樣式
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);
}
}
// 創建每一行
for (var i = startRow; i < ds.Tables[0].Rows.Count; i++)
{
var dr = ds.Tables[0].Rows[i];
//創建第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
{
//創建第i行的第j列
cell = row.CreateCell(j);
// 插入第j列的數據
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);
}
}
}
//生成文件在服務器上
using (var fs = new FileStream(saveFileName, FileMode.OpenOrCreate, FileAccess.Write))
{
wb.Write(fs);
}
return true;
}
catch (Exception er)
{
throw new Exception(er.Message);
}
}
6.從DataSet導出到MemoryStream流2007：
/// <summary>
/// 從DataSet導出到MemoryStream流2007
/// </summary>
/// <param name="saveFileName">文件保存路徑</param>
/// <param name="sheetName">Excel文件中的Sheet名稱</param>
/// <param name="ds">存儲數據的DataSet</param>
/// <param name="startRow">從哪一行開始寫入，從0開始</param>
/// <param name="datatypes">DataSet中的各列對應的數據類型</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;
}
}
}
//創建表頭
var row = sheet.CreateRow(0);
//樣式
var style1 = wb.CreateCellStyle();
//字體
var font1 = wb.CreateFont();
//字體顏色
font1.Color = HSSFColor.White.Index;
//字體加粗樣式
font1.Boldweight = (short)FontBoldWeight.Bold;
//style1.FillBackgroundColor = HSSFColor.WHITE.index;
//GetXLColour(wb, LevelOneColor);
// 設置圖案色
style1.FillForegroundColor = HSSFColor.Green.Index;
//GetXLColour(wb, LevelOneColor);// 設置背景色
style1.FillPattern = FillPattern.SolidForeground;
//樣式裡的字體設置具體的字體樣式
style1.SetFont(font1);
//文字水平對齊方式
style1.Alignment = HorizontalAlignment.Center;
//文字垂直對齊方式
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
{
//創建第0行的第j列
cell = row.CreateCell(j);
//單元格式設置樣式
cell.CellStyle = style1;
try
{
cell.SetCellValue(columnValue.ToString());
}
catch (Exception ex)
{
throw new Exception(ex.Message);
}
}
catch (Exception ex)
{
throw new Exception(ex.Message);
}
}
// 創建每一行
for (var i = startRow; i < ds.Tables[0].Rows.Count; i++)
{
var dr = ds.Tables[0].Rows[i];
//創建第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
{
//創建第i行的第j列
cell = row.CreateCell(j);
// 插入第j列的數據
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);
}
}
}
//生成文件在服務器上
using (var fs = new FileStream(saveFileName, FileMode.OpenOrCreate, FileAccess.Write))
{
wb.Write(fs);
}
return true;
}
catch (Exception er)
{
throw new Exception(er.Message);
}
}
7.讀Excel-根據NpoiDataType創建的DataTable列的數據類型：
/// <summary>
/// 讀Excel-根據NpoiDataType創建的DataTable列的數據類型
/// </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>
/// 讀Excel-得到不同數據類型單元格的數據
/// </summary>
/// <param name="datatype">數據類型</param>
/// <param name="row">數據中的一行</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>
/// 獲取單元格數據類型
/// </summary>
/// <param name="hs">單元格對象</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.總結：
本文是接著上五篇介紹.NET組件，目的只是在於總結一些組件的用法，將文章作為一個引子，各位讀者可以根據文章的介紹更加深入的去了解相關組件。有些地方寫的有誤，還望多多包涵和指正，歡迎大家給我建議介紹一些你們在項目中經常使用的組件，可以跟大家做一個分享。
