Shiny 正在尝试将闪亮应用程序数据（csv）写入桌面上的文件夹。警告：文件中有错误：无法打开连接

我是shiny的新手，正在尝试创建一个调查，在那里提交的数据将下载到我桌面上的一个文件夹中

我使用本文作为指导，基本上有完全相同的代码，但使用了“本地存储”选项来保存数据

当我运行应用程序时，文件被保存到我桌面上的正确文件夹中，但当我在shinyapps.io上发布并尝试使用url提交响应时，我收到错误： 文件中的警告（文件，ifelse（附加“a”、“w”） 和 无法打开文件“C:/Users/tolson/Desktop/shinny/1524841166_57edadaa8d9c46a94f5bb4a352412699.csv”：没有这样的文件或目录 2018-04-27T14:59:26.847383+00:00 shinyapps[331397]：警告：文件错误：无法打开连接

这与shiny的写作权限有关吗？我已经花了大量时间进行研究，但运气不好。任何帮助或见解都将不胜感激。提前谢谢

Code: 
library(shiny)

# Define the fields we want to save from the form
fields <- c("name", "dog", "food")

# Save a response
# ---- This is one of the two functions we will change for every storage 
type ----
saveData <- function(data) {
  data <- as.data.frame(t(data))
  if (exists("responses")) {
    responses <<- rbind(responses, data)
  } else {
    responses <<- data
  }

代码：
图书馆（闪亮）
#定义要从表单保存的字段
shinyapps.io上的服务器不能只将文件写入您的桌面。但是，您可以使用Dropbox，如所述。谢谢@GregordeCillia，非常感谢。
# Load all previous responses
# ---- This is one of the two functions we will change for every storage 
type ----
loadData <- function() {
  if (exists("responses")) {
    responses
  }
}

# Shiny app with 3 fields that the user can submit data for
shinyApp(
  ui = fluidPage(
    DT::dataTableOutput("responses", width = 300), tags$hr(),
    textInput("name", "Name", ""),
    textInput("dog", "what is your favorite dog?"),
    textInput("food", "favorite food?"),
    actionButton("submit", "Submit")
  ),
  server = function(input, output, session) {

# Whenever a field is filled, aggregate all form data
    formData <- reactive({
      data <- sapply(fields, function(x) input[[x]])
      data
    })

# When the Submit button is clicked, save the form data
    observeEvent(input$submit, {
      saveData(formData())
    })

# Show the previous responses
# (update with current response when Submit is clicked)
    output$responses <- DT::renderDataTable({
      input$submit
      loadData()
    })     
    outputDir <- "C:/Users/tolson/Desktop/Shiny"

    saveData <- function(data) {
      data <- t(data)
      # Create a unique file name
      fileName <- sprintf("%s_%s.csv", as.integer(Sys.time()), 
digest::digest(data))
      # Write the file to the local system
      write.csv(
        x = data,
        file = file.path(outputDir, fileName), 
        row.names = FALSE, quote = TRUE
      )
    }

    loadData <- function() {
       # Read all the files into a list
      files <- list.files(outputDir, full.names = TRUE)
      data <- lapply(files, read.csv, stringsAsFactors = FALSE) 
      # Concatenate all data together into one data.frame
      data <- do.call(rbind, data)
      data
    }





     }
 )