R Shiny — 无需上传即可获取文件大小？

Question

有没有办法在不将文件上传到 R Shiny 的情况下“查看”​​文件大小？

Answer 1

根据@ismirsehregal提供的建议，我们可以修改fileInput并添加一些JS来实现您的目标。

library(shiny)
ui <- fluidPage(
    fileInput("check", NULL, buttonLabel = "Upload to check", placeholder = "Check File Size"),
    # remove progress bar since we are not truely uploading
    tags$style("#check .shiny-file-input-progress {display: none}"), 
    tags$script(
        "
        $('#check').on('change', function() {
          $(this)
            .parents('div.input-group')
            .find('.form-control')
            .attr('placeholder', `File size is ${this.files[0].size}`); // update text
            
          // If you want R server to also know the size, we can set up an input 
          Shiny.setInputValue('check_size', this.files[0].size)
          $(this).val(''); // this prevents shiny to takeover the file and upload the file
        });
        "
    )
)
server <- function(input, output, session) {
    observe(print(input$check_size))
}


shinyApp(ui, server)

这将为您提供 UI 和服务器上的文件大小。希望这是你想要的。