/// <summary>
/// DataTable导出到Excel的MemoryStream Export()
/// </summary>
/// <param name="dtSource">DataTable数据源</param>
/// <param name="excelConfig">导出设置包含文件名、标题、列设置</param>
public static MemoryStream ExportMemoryStream(List <T> lists, ExcelConfig excelConfig)
{
HSSFWorkbook workbook = new HSSFWorkbook();
ISheet sheet = workbook.CreateSheet();
Type type = typeof(T);
//PropertyInfo[] properties = type.GetProperties();
#region 右击文件 属性信息
{
DocumentSummaryInformation dsi = PropertySetFactory.CreateDocumentSummaryInformation();
dsi.Company = "NPOI";
workbook.DocumentSummaryInformation = dsi;
SummaryInformation si = PropertySetFactory.CreateSummaryInformation();
si.Author = ""; //填加xls文件作者信息
si.ApplicationName = ""; //填加xls文件创建程序信息
si.LastAuthor = ""; //填加xls文件最后保存者信息
si.Comments = ""; //填加xls文件作者信息
si.Title = ""; //填加xls文件标题信息
si.Subject = ""; //填加文件主题信息
si.CreateDateTime = System.DateTime.Now;
workbook.SummaryInformation = si;
}
//网格线
sheet.DisplayGridlines = true;
#endregion
#region 设置标题样式
//导出的列数
int excelcolumnsLen = excelConfig.ColumnEntity.Count;
ICellStyle headStyle = workbook.CreateCellStyle();
int[] arrColWidth = new int[excelcolumnsLen];
string[] arrColName = new string[excelcolumnsLen]; //列名
ICellStyle[] arryColumStyle = new ICellStyle[excelcolumnsLen]; //样式表
headStyle.Alignment = HorizontalAlignment.Center; // ------------------
if (excelConfig.Background != new Color())
{
if (excelConfig.Background != new Color())
{
headStyle.FillPattern = FillPattern.SolidForeground;
headStyle.FillForegroundColor = GetXLColour(workbook, excelConfig.Background);
}
}
IFont font = workbook.CreateFont();
font.FontHeightInPoints = excelConfig.TitlePoint;
if (excelConfig.ForeColor != new Color())
{
font.Color = GetXLColour(workbook, excelConfig.ForeColor);
}
font.Boldweight = 700;
headStyle.SetFont(font);
#endregion
#region 列头及样式
ICellStyle cHeadStyle = workbook.CreateCellStyle();
cHeadStyle.Alignment = HorizontalAlignment.Center; // ------------------
IFont cfont = workbook.CreateFont();
cfont.FontHeightInPoints = excelConfig.HeadPoint;
cHeadStyle.SetFont(cfont);
//有边框
cHeadStyle.BorderBottom = BorderStyle.Thin;
cHeadStyle.BorderLeft = BorderStyle.Thin;
cHeadStyle.BorderRight = BorderStyle.Thin;
cHeadStyle.BorderTop = BorderStyle.Thin;
#endregion
#region 设置内容单元格样式
int i = 0;
foreach (ColumnEntity expEntity in excelConfig.ColumnEntity)
{
string columnName = expEntity.Column;
ICellStyle columnStyle = workbook.CreateCellStyle();
columnStyle.Alignment = HorizontalAlignment.Center;
// arrColWidth[i] = Encoding.GetEncoding(936).GetBytes(column.Name).Length;
//arrColName[i] = columnName;
var columnentity = expEntity;
//ColumnEntity columnentity = excelConfig.ColumnEntity.Find(t => t.Column == column.Name);
//if (columnentity != null)
//{
arrColName[i] = columnentity.ExcelColumn;
if (columnentity.Width != 0)
{
arrColWidth[i] = columnentity.Width;
}
if (columnentity.Background != new Color())
{
if (columnentity.Background != new Color())
{
columnStyle.FillPattern = FillPattern.SolidForeground;
columnStyle.FillForegroundColor = GetXLColour(workbook, columnentity.Background);
}
}
if (columnentity.Font != null || columnentity.Point != 0 || columnentity.ForeColor != new Color())
{
IFont columnFont = workbook.CreateFont();
columnFont.FontHeightInPoints = 10;
if (columnentity.Font != null)
{
columnFont.FontName = columnentity.Font;
}
if (columnentity.Point != 0)
{
columnFont.FontHeightInPoints = columnentity.Point;
}
if (columnentity.ForeColor != new Color())
{
columnFont.Color = GetXLColour(workbook, columnentity.ForeColor);
}
columnStyle.SetFont(font);
}
//}
arryColumStyle[i] = columnStyle;
i++;
}
#endregion
#region 填充数据
#endregion
ICellStyle dateStyle = workbook.CreateCellStyle();
IDataFormat format = workbook.CreateDataFormat();
dateStyle.DataFormat = format.GetFormat("yyyy-mm-dd");
int rowIndex = 0;
foreach (T item in lists)
{
#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();
}
#region 表头及样式
{
if (excelConfig.Title != null)
{
IRow headerRow = sheet.CreateRow(0);
if (excelConfig.TitleHeight != 0)
{
headerRow.Height = (short)(excelConfig.TitleHeight * 20);
}
headerRow.HeightInPoints = 25;
headerRow.CreateCell(0).SetCellValue(excelConfig.Title);
headerRow.GetCell(0).CellStyle = headStyle;
sheet.AddMergedRegion(new NPOI.SS.Util.CellRangeAddress(0, 0, 0, excelConfig.ColumnEntity.Count)); // ------------------
}
}
#endregion
#region 列头及样式
{
IRow headerRow = sheet.CreateRow(1);
#region 如果设置了列标题就按列标题定义列头，没定义直接按字段名输出
int headIndex = 0;
foreach (var aaa in excelConfig.ColumnEntity)
{
headerRow.CreateCell(headIndex).SetCellValue(arrColName[headIndex]);
headerRow.GetCell(headIndex).CellStyle = cHeadStyle;
//设置列宽
sheet.SetColumnWidth(headIndex, (arrColWidth[headIndex] + 1) * 256);
headIndex++;
}
#endregion
}
#endregion
rowIndex = 2;
}
#endregion
#region 填充内容
IRow dataRow = sheet.CreateRow(rowIndex);
int ordinal = 0;
foreach (ColumnEntity expEntity in excelConfig.ColumnEntity)
{
ICell newCell = dataRow.CreateCell(ordinal);
newCell.CellStyle = arryColumStyle[ordinal];
//find the property type
PropertyInfo p = type.GetProperty(expEntity.Column);
var columnType = p.PropertyType;
if (p.PropertyType.IsGenericType && p.PropertyType.GetGenericTypeDefinition() == typeof(Nullable <>))
{
// If it is NULLABLE, then get the underlying type. eg if "Nullable<int>" then this will return just "int"
columnType = p.PropertyType.GetGenericArguments()[0];
}
string drValue = p.GetValue(item, null) == null ? "" : p.GetValue(item, null).ToString();
SetCell(newCell, dateStyle, columnType, drValue);
ordinal++;
}
#endregion
rowIndex++;
}
//合并行
if (excelConfig.MergeRangeIndexArr != null)
{
SetCellMerge(sheet, excelConfig.MergeRangeIndexArr);
}
using (MemoryStream ms = new MemoryStream())
{
workbook.Write(ms);
ms.Flush();
ms.Position = 0;
return(ms);
}
}