Shiny||文件的上传与下载

library(shiny)
runExample("09_upload")

#UI
ui<-shinyUI(pageWithSidebar(
  headerPanel("CSV Viewer"),
  sidebarPanel(
    fileInput('file1', 'Choose CSV File',
              accept=c('text/csv', 'text/comma-separated-values,text/plain')),
    tags$hr(),
    checkboxInput('header', 'Header', TRUE),
    radioButtons('sep', 'Separator',
                 c(Comma=',',
                   Semicolon=';',
                   Tab='\t'),
                 'Comma'),
    radioButtons('quote', 'Quote',
                 c(None='',
                   'Double Quote'='"',
                   'Single Quote'="'"),
                 'Double Quote')
  ),
  mainPanel(
    tableOutput('contents')
  )
))

#server.R
server<-shinyServer(function(input, output) {
  output$contents <- renderTable({
    
    # input$file1 will be NULL initially. After the user selects and uploads a 
    # file, it will be a data frame with 'name', 'size', 'type', and 'datapath' 
    # columns. The 'datapath' column will contain the local filenames where the 
    # data can be found.

    inFile <- input$file1

    if (is.null(inFile))
      return(NULL)
    
    read.csv(inFile$datapath, header=input$header, sep=input$sep, quote=input$quote)
  })
})
shinyApp(ui,server)

library(shiny)
runExample("10_download")

library(shiny)

# Define UI for data download app ----
ui <- fluidPage(

  # App title ----
  titlePanel("Downloading Data"),

  # Sidebar layout with input and output definitions ----
  sidebarLayout(

    # Sidebar panel for inputs ----
    sidebarPanel(

      # Input: Choose dataset ----
      selectInput("dataset", "Choose a dataset:",
                  choices = c("rock", "pressure", "cars")),

      # Button
      downloadButton("downloadData", "Download")

    ),

    # Main panel for displaying outputs ----
    mainPanel(

      tableOutput("table")

    )

  )
)

# Define server logic to display and download selected file ----
server <- function(input, output) {

  # Reactive value for selected dataset ----
  datasetInput <- reactive({
    switch(input$dataset,
           "rock" = rock,
           "pressure" = pressure,
           "cars" = cars)
  })

  # Table of selected dataset ----
  output$table <- renderTable({
    datasetInput()
  })

  # Downloadable csv of selected dataset ----
  output$downloadData <- downloadHandler(
    filename = function() {
      paste(input$dataset, ".csv", sep = "")
    },
    content = function(file) {
      write.csv(datasetInput(), file, row.names = FALSE)
    }
  )

}

# Create Shiny app ----
shinyApp(ui, server)