scala中把dataframe写到excel代码

可以使用以下代码将DataFrame写入Excel文件：

import org.apache.spark.sql.DataFrame
import org.apache.poi.ss.usermodel.WorkbookFactory
import org.apache.poi.ss.usermodel.Workbook
import org.apache.poi.ss.usermodel.Sheet
import org.apache.poi.ss.usermodel.Row
import org.apache.poi.ss.usermodel.Cell
import java.io.FileOutputStream

def writeDataFrameToExcel(dataFrame: DataFrame, filePath: String, sheetName: String) = {
  val workbook: Workbook = WorkbookFactory.create(true)
  val sheet: Sheet = workbook.createSheet(sheetName)
  val headerRow: Row = sheet.createRow(0)
  val columns = dataFrame.columns
  for (i <- 0 until columns.length) {
    val cell: Cell = headerRow.createCell(i)
    cell.setCellValue(columns(i))
  }
  val rows = dataFrame.collect()
  for (i <- 0 until rows.length) {
    val row: Row = sheet.createRow(i + 1)
    for (j <- 0 until columns.length) {
      val cell: Cell = row.createCell(j)
      cell.setCellValue(rows(i).get(j).toString)
    }
  }
  val fileOut = new FileOutputStream(filePath)
  workbook.write(fileOut)
  fileOut.close()
}

其中，dataFrame是要写入Excel文件的DataFrame，filePath是Excel文件的路径，sheetName是Excel文件中的工作表名称。