闪亮的应用程序上传和下载数据动态不工作

Question

我是超级新的闪亮的应用程序，所以我感谢您的帮助这一点！我的代码目前已被破坏，我不知道为什么。

以下是我的问题：

1. 如何使这些代码工作？我希望用户上传一个csv文件，在datatable中查看它，然后下载datatable
2. 如何使用列中的正则表达式过滤行？我希望这个正则表达式应用df[with(df, grepl("\\bDATE\\b|\\b[0-9]{4}-[0-9]{2}-[0-9]{2}\\b|\\b[0-9]{2}-[0-9]{2}\\b|[0-9]{4}\\b", close_notes)),]。您可以假设每个csv文件都将该列作为数据的一部分(在示例中是close_notes)。

谢谢!我的密码在下面。

library(shiny)

ui <- fluidPage(
    sidebarLayout(
        sidebarPanel(
            fileInput("file1", "Choose CSV File",
                      accept = c(
                          "text/csv",
                          "text/comma-separated-values,text/plain",
                          ".csv")
            ),
            tags$hr(),
            checkboxInput("header", "Header", TRUE),
            
            # Button
            downloadButton("downloadData", "Download")
            
        ),
        mainPanel(
            dataTableOutput("contents")
        )
    )
)




server <- function(input, output) {

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

shinyApp(ui, server)

Answer 1

尝尝这个

library(shiny)

ui <- fluidPage(
  sidebarLayout(
    sidebarPanel(
      fileInput("file1", "Choose CSV File",
                accept = c(
                  "text/csv",
                  "text/comma-separated-values,text/plain",
                  ".csv")
      ),
      tags$hr(),
      checkboxInput("header", "Header", TRUE),
      
      # Button
      downloadButton("downloadData", "Download")
      
    ),
    mainPanel(
      dataTableOutput("contents")
    )
  )
)

server <- function(input, output) {
  
  datasetInput <- reactive({
    req(input$file1)
    # input$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)
  })
  
  output$contents <- renderDataTable({
    datasetInput()
  })
  
  output$downloadData <- downloadHandler(
    filename = function() {
      paste("myfile",Sys.Date(), ".csv", sep = "")
    },
    content = function(file) {
      write.csv(datasetInput(), file, row.names = FALSE)
    }
  )
}

shinyApp(ui, server)