How to upload multiple tables and display them separately in r shiny?

Question

I want to upload multiple tables and display them separately.

For example: I would like to upload N tables (I don't know N in advance) and want to display them in the main panel as:

Table1:

Table2:

Table3:

.....

My code is shown below but it did not work. How to change it?

ui <- fluidPage(
  sidebarLayout(
    sidebarPanel(
      fileInput(
        inputId = "calfile", 
        label = "Choose CSV File", 
        multiple = TRUE,
        accept = c("text/csv",
                   "text/comma-separated-values,text/plain",
                   ".csv")
      )
    ),
    mainPanel(
      tableOutput("contents")
    )
  )
)

server <- function(input, output) {

  data<-reactive({

    if (is.null(input$calfile))
      return()
    else
    {
      nfile<-nrow(input$calfile)

      csv=list()

      for(i in 1: nfile)
      {
        csv[[i]]=read.csv(input$calfile$datapath[i])

      }

      }

  })


  output$contents<-  renderTable(data())
}

shinyApp(ui, server)

Many thanks.

Answer 1

Here is an example that may be helpful:

https://stackoverflow.com/a/35943224/3460670

Edit: Try this for your server for creating N tables. You can read in your N data files in a list, and dynamically create outputs for the N tables in an observe expression.

server <- function(input, output) {

  observe({
    if (!is.null(input$calfile)) {
      N_tables = length(input$calfile[, 1])

      upload <- list()
      for (i in 1:N_tables) {
        upload[[i]] <- read.csv(input$calfile$datapath[i])
      }

      output$contents <- renderUI({
        table_output_list <- lapply(1:N_tables, function(i) {
          tableOutput(paste0("table_name", i))
        })
        do.call(tagList, table_output_list)
      })

      for (i in 1:N_tables) {
        local({
          my_i <- i
          output[[paste0("table_name", my_i)]] <- renderTable({
            upload[[my_i]]
          })
        })
      }
    }
  })

}