我试图重现你的问题，但saveWorkbook显示空白单元格时，NA是你想要的。你尝试更新openxlsx？

library(openxlsx)

wb <- createWorkbook()
addWorksheet(wb, "test")
writeData(wb, "test", c(1, NA, 2), startCol = 1, startRow = 1)

mystyle <- createStyle(border = "Left")
addStyle(wb, sheet = "test", style = mystyle,
         row = 1, cols = 2, gridExpand = T)
  
saveWorkbook(wb, "C:/Users/pc36957/Documents/myresult.xlsx", overwrite = T)

**编辑：**问题不是来自openxlsx版本。另一种方法似乎是使用readWorkbook临时从工作表中提取值，然后使用writeData的keepNA = F参数重写它们。

# Open file
wb <- loadWorkbook("C:/myfile.xlsx")

# temporarily extract sheet as df
temp <- readWorkbook(wb, sheet = "Sheet1", skipEmptyRows = F)

# rewrite data to same sheet
writeData(wb, "Sheet1", temp, keepNA = F, startCol = 1, startRow = 1)

# Formatting
mystyle <- createStyle(border = "Left" )
addStyle(wb, sheet = "Sheet1", style = mystyle, row = 1, cols = 2, gridExpand = T)

# Save saveWorkbook
(wb, "C:/myresult.xlsx", overwrite = T)