• 生成csv格式文件并导出至页面的前后台实现


    一、前台实现:

    1. HTML:

    <div>
      <a href="javascript:void(0);" class="btnStyleLeft">
    	<span class="fa fa-external-link" onclick="test.exportGridData()">导出</span>
      </a>
    </div>

    2.js:

    /*导出查询记录到本地下载目录*/
        exportGridData: function(type) {
    	var exportIFrame = document.createElement("iframe");
    	exportIFrame.src = "/ipeg-web/requestDispatcher?" + exportParams.join("&");  // exportParams带入需要传至后台的参数
    	exportIFrame.style.display = "none";
    	document.body.appendChild(exportIFrame);
    },
    

     

    二、后台实现:

     1、ExtensionMode枚举---用于csv/txt/excel2003/excel2007文件的写入 

    import com.csvreader.CsvWriter;
    import com.google.common.base.Charsets;
    import com.google.common.base.Joiner;
    import com.google.common.base.Preconditions;
    import org.apache.poi.hssf.usermodel.HSSFCellStyle;
    import org.apache.poi.hssf.usermodel.HSSFFont;
    import org.apache.poi.hssf.usermodel.HSSFWorkbook;
    import org.apache.poi.ss.usermodel.*;
    import org.apache.poi.xssf.usermodel.XSSFCell;
    import org.apache.poi.xssf.usermodel.XSSFWorkbook;
    import java.io.IOException;
    import java.io.OutputStream;
    import java.util.List;
    
    public enum ExtensionMode {
        TXT(".txt", "application/octet-stream") {
            @Override
            public void write(List<String[]> lines, String[] header, OutputStream outputStream) throws IOException {
                checkNotNull(lines, header, outputStream);
                final String headerString = Joiner.on(",").useForNull("").join(header);
                outputStream.write((headerString + "
    ").getBytes(Charsets.UTF_8));
                for (String[] parts : lines) {
                    final String line = Joiner.on(",").useForNull("").join(parts);
                    outputStream.write((line + "
    ").getBytes(Charsets.UTF_8));
                }
            }
        },
        CSV(".csv", "application/octet-stream") {
            @Override
            public void write(List<String[]> lines, String[] header, OutputStream outputStream) throws IOException {
                checkNotNull(lines, header, outputStream);
                final CsvWriter csvWriter = new CsvWriter(outputStream, ',', Charsets.UTF_8);
                try {
                    csvWriter.writeRecord(header);
                    for (String[] parts : lines) {
                        csvWriter.writeRecord(parts);
                    }
                    csvWriter.flush();
                } finally {
                    csvWriter.close();
                }
            }
        },
        EXCEL2003(".xls", "application/vnd.ms-excel") {
            @Override
            public void write(List<String[]> lines, String[] header, OutputStream outputStream) throws IOException {
                checkNotNull(lines, header, outputStream);
                final Workbook workbook = new ExcelMaker() {
                    @Override
                    protected Workbook createWorkbook() {
                        return new HSSFWorkbook();
                    }
                }.make(lines, header);
                workbook.write(outputStream);
            }
        },
        EXCEL2007(".xlsx", "application/vnd.ms-excel") {
            @Override
            public void write(List<String[]> lines, String[] header, OutputStream outputStream) throws IOException {
                checkNotNull(lines, header, outputStream);
                final Workbook workbook = new ExcelMaker() {
                    @Override
                    protected Workbook createWorkbook() {
                        return new XSSFWorkbook();
                    }
                }.make(lines, header);
                workbook.write(outputStream);
            }
        };
        private static void checkNotNull(List<String[]> lines, String[] header, OutputStream outputStream) {
            Preconditions.checkNotNull(lines, "null list for write");
            Preconditions.checkNotNull(header, "null header");
            Preconditions.checkNotNull(outputStream, "null output stream ");
        }
        private final String suffix;
        private final String contentType;
    
        ExtensionMode(String suffix, String contentType) {
            this.suffix = suffix;
            this.contentType = contentType;
        }
    
        public String getSuffix() {
            return suffix;
        }
    
        public String getContentType() {
            return contentType;
        }
    
        public static ExtensionMode getExtensionModeBySuffix(String suffix) {
            for (ExtensionMode mode : ExtensionMode.values()) {
                if (mode.getSuffix().equalsIgnoreCase(suffix))
                    return mode;
            }
            throw new IllegalArgumentException("Unknown File Type.");
        }
    
        public abstract void write(List<String[]> lines, String[] header, OutputStream outputStream)
                throws IOException;
    
        private abstract static class ExcelMaker {
            public Workbook make(List<String[]> lines, String[] header) {
                Workbook wb = createWorkbook();
                Sheet sheet = wb.createSheet("数据源");
                // 创建格式
                CellStyle cellStyle = getCellStyle(wb);
                // 添加第一行标题
                addHeader(header, sheet, cellStyle);
                // 从第二行开始写入数据
                addData(lines, sheet, cellStyle);
                return wb;
            }
    
            private void addData(List<String[]> lines, Sheet sheet, CellStyle cellStyle) {
                for (int sn = 0; sn < lines.size(); sn++) {
                    String[] col = lines.get(sn);
                    Row row = sheet.createRow(sn + 1);
                    for (int cols = 0; cols < col.length; cols++) {
                        Cell cell = row.createCell(cols);
                        cell.setCellStyle(cellStyle);
                        cell.setCellType(XSSFCell.CELL_TYPE_STRING);
                        cell.setCellValue(col[cols]);
                    }
                }
            }
    
            private CellStyle getCellStyle(Workbook wb) {
                Font font = wb.createFont();
                font.setColor(HSSFFont.COLOR_NORMAL);
                font.setBoldweight(HSSFFont.BOLDWEIGHT_NORMAL);
                CellStyle cellStyle = wb.createCellStyle();
                cellStyle.setFont(font);
                cellStyle.setAlignment(HSSFCellStyle.ALIGN_CENTER);
                cellStyle.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);
                return cellStyle;
            }
    
            private void addHeader(String[] header, Sheet sheet, CellStyle cellStyle) {
                Row titleRow = sheet.createRow(0);
                // 创建第1行标题单元格
                for (int i = 0, size = header.length; i < size; i++) {
                    switch (i) {
                        case 5:
                        case 7:
                            sheet.setColumnWidth(i, 10000);
                            break;
                        default:
                            sheet.setColumnWidth(i, 3500);
                            break;
                    }
                    Cell cell = titleRow.createCell(i, 0);
                    cell.setCellStyle(cellStyle);
                    cell.setCellType(XSSFCell.CELL_TYPE_STRING);
                    cell.setCellValue(header[i]);
                }
            }
            protected abstract Workbook createWorkbook();
        }
    }
    

    2. dataExport:具体的数据导出

    public class dataExport {
        private final byte[] UTF_BOM = new byte[]{(byte) 0xEF, (byte) 0xBB, (byte) 0xBF};
        private final String[] header = new String[]{"user", "name", "id"};
        List logData = null;
        OutputStream outputStream = null;
        
      outputStream = response.getOutputStream(); try { export(ExtensionMode.CSV, header, getUserData(logData), outputStream); } catch (IOException e) { e.printStackTrace(); }finally{ if (outputStream != null) { try { outputStream.close(); } catch (Exception e) { e.printStackTrace(); } } } private void export(ExtensionMode extensionMode, String[] header, ImmutableList<String[]> lines, OutputStream outputStream) throws IOException { response.setContentType(extensionMode.getContentType() + ";charset=UTF-8"); response.reset(); response.setHeader("Content-Disposition", "attachment; filename=" + URLEncoder.encode(getFileName(extensionMode.getSuffix()), "UTF-8")); if (extensionMode == ExtensionMode.CSV) { outputStream.write(UTF_BOM); //防止中文乱码 } extensionMode.write(lines, header, outputStream); outputStream.flush(); } private String getFileName(String extension) { SimpleDateFormat format = new SimpleDateFormat("yyyyMMddHHmmss"); return format.format(new Date()) + extension; } public ImmutableList<String[]> getUserData(List<UserEntity> data) { return from(data).transform(new userDataFunction()).toList(); } private class userDataFunction implements Function<UserEntity, String[]> { @Override public String[] apply(UserEntity input) { return new String[]{ input.getName(), input.getUser(), input.getId() }; } } }

    3.需要添加的maven依赖如下:

    <dependency>
    <groupId>net.sf.opencsv</groupId>
    <artifactId>opencsv</artifactId>
    <version>1.8</version>
    </dependency>
    <dependency>
    <groupId>org.apache.poi</groupId>
    <artifactId>poi</artifactId>
    <version>3.9</version>
    </dependency>
    <dependency>
    <groupId>org.apache.poi-ooxml</groupId>
    <artifactId>poi-ooxml</artifactId>
    <version>3.7</version>
    </dependency>

    三、效果图如下:

      

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  • 原文地址:https://www.cnblogs.com/hunterCecil/p/5767507.html
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