/// <summary>
/// DataTable导出到Excel的MemoryStream
/// </summary>
/// <param name="dtSource">源DataTable</param>
/// <param name="strHeaderText">表头文本</param>
public static MemoryStream ExportDt(DataTable dtSource, string strHeaderText)
{
var workbook = new HSSFWorkbook();
var sheet = workbook.CreateSheet() as HSSFSheet;
var cellStyle = workbook.CreateBasicCellStyle();
HSSFCellStyle dateStyle = workbook.CreateBasicCellStyle();
var format = workbook.CreateDataFormat() as HSSFDataFormat;
// dateStyle.DataFormat = format.GetFormat("yyyy-mm-dd HH:mm:ss");
dateStyle.DataFormat = format.GetFormat("yyyy-mm-dd");
//取得列宽
int[] arrColWidth = new int[dtSource.Columns.Count];
foreach (DataColumn item in dtSource.Columns)
{
arrColWidth[item.Ordinal] = Encoding.GetEncoding(936).GetBytes(item.ColumnName).Length + 6;
}
for (int i = 0; i < dtSource.Rows.Count; i++)
{
for (int j = 0; j < dtSource.Columns.Count; j++)
{
int intTemp = Encoding.GetEncoding(936).GetBytes(dtSource.Rows[i][j].ToString()).Length;
if (intTemp > arrColWidth[j])
{
arrColWidth[j] = intTemp;
}
}
}
int rowIndex = 0;
foreach (DataRow row in dtSource.Rows)
{
#region 新建表，填充表头，填充列头，样式
if (rowIndex == 65535 || rowIndex == 0)
{
if (rowIndex != 0)
{
sheet = workbook.CreateSheet() as HSSFSheet;
}
#region 表头及样式
if (!string.IsNullOrEmpty(strHeaderText) && strHeaderText != "下载开票模板_Evan")
{
var headerRow = sheet.CreateRow(0) as HSSFRow;
headerRow.HeightInPoints = 25;
headerRow.CreateCell(0).SetCellValue(strHeaderText);
var headStyle = workbook.CreateCellStyle() as HSSFCellStyle;
headStyle.Alignment = NPOI.SS.UserModel.HorizontalAlignment.Center;
var font = workbook.CreateFont() as HSSFFont;
font.FontHeightInPoints = 16;
font.Boldweight = 700;
headStyle.SetFont(font);
headerRow.GetCell(0).CellStyle = headStyle;
sheet.AddMergedRegion(new CellRangeAddress(0, 0, 0, dtSource.Columns.Count - 1));
//headerRow.Dispose();
if (dtSource.Columns[dtSource.Columns.Count - 1].ColumnName == "编号")
{
sheet.SetColumnHidden(dtSource.Columns.Count - 1, true);
}
// sheet.SetColumnHidden();
}
#endregion
#region 列头及样式
{
var rownum = 0;
if (strHeaderText == "下载开票模板_Evan")
{
rownum = 0;
}
else
{
rownum = string.IsNullOrEmpty(strHeaderText) ? 0 : 1;
}
var headerRow = sheet.CreateRow(rownum) as HSSFRow;
headerRow.HeightInPoints = 20;
var headStyle = workbook.CreateCellStyle() as HSSFCellStyle;
headStyle.Alignment = NPOI.SS.UserModel.HorizontalAlignment.Center;
var font = workbook.CreateFont() as HSSFFont;
font.FontHeightInPoints = 11;
font.Boldweight = 600;
headStyle.SetFont(font);
headStyle.BorderLeft = BorderStyle.Thin;
headStyle.BorderRight = BorderStyle.Thin;
headStyle.BorderTop = BorderStyle.Thin;
headStyle.BorderBottom = BorderStyle.Thin;
foreach (DataColumn column in dtSource.Columns)
{
if (strHeaderText == "下载开票模板_Evan")
{
//headStyle.IsLocked = true;
headerRow.CreateCell(column.Ordinal).CellStyle = headStyle;
sheet.SetColumnWidth(column.Ordinal, (arrColWidth[column.Ordinal] + 1) * 256);
headerRow.CreateCell(column.Ordinal).SetCellValue(column.ColumnName);
}
else
{
headerRow.CreateCell(column.Ordinal).SetCellValue(column.ColumnName);
headerRow.GetCell(column.Ordinal).CellStyle = headStyle;
//设置列宽
//sheet.SetColumnWidth(column.Ordinal, (arrColWidth[column.Ordinal] + 1) * 256);
}
}
//sheet.CreateFreezePane(0, 1, 0, 1);
//sheet.CreateFreezePane(1, 0, 1, 0);
//headerRow.Dispose();
}
#endregion
if (strHeaderText == "下载开票模板_Evan")
{
rowIndex = 1;
}
else
{
rowIndex = string.IsNullOrEmpty(strHeaderText) ? 1 : 2;
}
}
#endregion
#region 填充内容
var dataRow = sheet.CreateRow(rowIndex) as HSSFRow;
foreach (DataColumn column in dtSource.Columns)
{
var newCell = dataRow.CreateCell(column.Ordinal) as HSSFCell;
newCell.CellStyle = cellStyle;
string drValue = row[column].ToString();
#region 写单元格的值
switch (column.DataType.ToString())
{
case "System.String": //字符串类型
double result;
if (IsNumeric(drValue, out result))
{
double.TryParse(drValue, out result);
newCell.SetCellValue(result);
break;
}
else
{
newCell.SetCellValue(drValue);
break;
}
case "System.DateTime": //日期类型
DateTime dateV;
if (DateTime.TryParse(drValue, out dateV))
{
newCell.SetCellValue(dateV);
newCell.CellStyle = dateStyle; //格式化显示
}
break;
case "System.Boolean": //布尔型
bool boolV = false;
bool.TryParse(drValue, out boolV);
newCell.SetCellValue(boolV);
break;
case "System.Int16": //整型
case "System.Int32":
case "System.Int64":
case "System.Byte":
int intV = 0;
int.TryParse(drValue, out intV);
newCell.SetCellValue(intV);
break;
case "System.Decimal": //浮点型
case "System.Double":
double doubV = 0;
double.TryParse(drValue, out doubV);
newCell.SetCellValue(doubV);
break;
case "System.DBNull": //空值处理
newCell.SetCellValue("");
break;
default:
newCell.SetCellValue(drValue);
break;
}
#endregion
if (strHeaderText == "下载开票模板_Evan")
{
if (column.ColumnName == "Booking Branch" || column.ColumnName == "Customer ID" || column.ColumnName == "EBBS relationship ID" || column.ColumnName == "Customer ID/counterparty ID" || column.ColumnName == "EBBS Master ID" || column.ColumnName == "分行代码" || column.ColumnName == "客户编码")
{
newCell.SetCellValue(drValue);
}
}
}
#endregion
rowIndex++;
}
using (var ms = new MemoryStream())
{
workbook.Write(ms);
ms.Flush();
ms.Position = 0;
//sheet.Dispose();
//workbook.Dispose();
return(ms);
}
}
