3.3 用NPOI操作EXCEL－－生成一张工资单

这一节，我们将综合NPOI的常用功能（包括创建和填充单元格、合并单元格、设置单元格样式和利用公式），做一个工资单的实例。先看创建标题行的代码：

//写标题文本
HSSFSheet sheet1 = hssfworkbook.CreateSheet("Sheet1");
HSSFCell cellTitle = sheet1.CreateRow(0).CreateCell(0);
cellTitle.SetCellValue("XXX公司2009年10月工资单");

//设置标题行样式
HSSFCellStyle style = hssfworkbook.CreateCellStyle();
style.Alignment = HSSFCellStyle.ALIGN_CENTER;
HSSFFont font = hssfworkbook.CreateFont();
font.FontHeight = 20 * 20;
style.SetFont(font);

cellTitle.CellStyle = style;

//合并标题行
sheet1.AddMergedRegion(new Region(0, 0, 1, 6));

其中用到了我们前面讲的设置单元格样式和合并单元格等内容。接下来我们循环创建公司每个员工的工资单：

DataTable dt=GetData();
HSSFRow row;
HSSFCell cell;
HSSFCellStyle celStyle=getCellStyle();

HSSFPatriarch patriarch = sheet1.CreateDrawingPatriarch();
HSSFClientAnchor anchor;
HSSFSimpleShape line;
int rowIndex;
for (int i = 0; i < dt.Rows.Count; i++)
{
    //表头数据
    rowIndex = 3 * (i + 1);
    row = sheet1.CreateRow(rowIndex);

    cell = row.CreateCell(0);
    cell.SetCellValue("姓名");
    cell.CellStyle = celStyle;

    cell = row.CreateCell(1);
    cell.SetCellValue("基本工资");
    cell.CellStyle = celStyle;

    cell = row.CreateCell(2);
    cell.SetCellValue("住房公积金");
    cell.CellStyle = celStyle;

    cell = row.CreateCell(3);
    cell.SetCellValue("绩效奖金");
    cell.CellStyle = celStyle;

    cell = row.CreateCell(4);
    cell.SetCellValue("社保扣款");
    cell.CellStyle = celStyle;

    cell = row.CreateCell(5);
    cell.SetCellValue("代扣个税");
    cell.CellStyle = celStyle;

    cell = row.CreateCell(6);
    cell.SetCellValue("实发工资");
    cell.CellStyle = celStyle;

    DataRow dr = dt.Rows[i];
    //设置值和计算公式
    row = sheet1.CreateRow(rowIndex + 1);
    cell = row.CreateCell(0);
    cell.SetCellValue(dr["FName"].ToString());
    cell.CellStyle = celStyle;

    cell = row.CreateCell(1);
    cell.SetCellValue((double)dr["FBasicSalary"]);
    cell.CellStyle = celStyle;

    cell = row.CreateCell(2);
    cell.SetCellValue((double)dr["FAccumulationFund"]);
    cell.CellStyle = celStyle;

    cell = row.CreateCell(3);
    cell.SetCellValue((double)dr["FBonus"]);
    cell.CellStyle = celStyle;

    cell = row.CreateCell(4);
    cell.SetCellFormula(String.Format("$B{0}*0.08",rowIndex+2));
    cell.CellStyle = celStyle;

    cell = row.CreateCell(5);
    cell.SetCellFormula(String.Format("SUM($B{0}:$D{0})*0.1",rowIndex+2));
    cell.CellStyle = celStyle;

    cell = row.CreateCell(6);
    cell.SetCellFormula(String.Format("SUM($B{0}:$D{0})-SUM($E{0}:$F{0})",rowIndex+2));
    cell.CellStyle = celStyle;

    //绘制分隔线
    sheet1.AddMergedRegion(new Region(rowIndex+2, 0, rowIndex+2, 6));
    anchor = new HSSFClientAnchor(0, 125, 1023, 125, 0, rowIndex + 2, 6, rowIndex + 2);
    line = patriarch.CreateSimpleShape(anchor);
    line.ShapeType = HSSFSimpleShape.OBJECT_TYPE_LINE;
    line.LineStyle = HSSFShape.LINESTYLE_DASHGEL;

}

其中为了文件打印为单元格增加了黑色边框的样式（如果不设置边框样式，打印出来后是没有边框的）。另外，注意循环过程中excel中的行号随数据源中的行号变化处理。完整代码如下：