如何在闪亮的应用程序过滤器/按钮中应用正则表达式？

如何解决如何在闪亮的应用程序过滤器/按钮中应用正则表达式？

我是 Shiny Apps 和 R 的新手。我将如何添加一个按钮来允许我使用这个正则表达式过滤传入的数据集？上传的数据集都包含相同的列名，我想应用正则表达式的列是“close_notes”。我想首先将此列转换为字符串，将所有内容大写，然后应用正则表达式。非常感谢您提前提供帮助！

正则表达式：

"\\bMASTER DATA\\b|\\bSOURCE LIST\\b|\\bVALIDITY DATES\\b|\\bMRP CONTROLLER\\b|\\bPSV\\b|\\bELIGIBILITY\\b|\\bCOST\\b|\\bMARKETING EXCLUSION\\b|\\bEFFECTIVITY\\b|\\bMISSING\\b|\bbBLANK\\b"

以下代码适用于 Shiny 应用程序。如果有任何问题或应该修改，请告诉我。谢谢！

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)

解决方法

您应该将单词边界移动到交替的外部，如下所示：

\b(MASTER DATA|SOURCE LIST|VALIDITY DATES|MRP CONTROLLER|PSV|ELIGIBILITY|COST|MARKETING EXCLUSION|EFFECTIVITY|MISSING|BLANK)\b

,

您可以对当前代码进行一些更改。

• 使用 reactive 保存上传的数据，也将 observe 更改为 actionButton。
• 添加了一个 observeEvent 以在按下按钮后应用过滤器并在服务器端使用 library(shiny) library(dplyr) #Define the regex to apply. regex_to_apply <- "\\bMASTER DATA..." ui <- fluidPage( sidebarLayout( sidebarPanel( fileInput("file1","Choose CSV File",accept = c( "text/csv","text/comma-separated-values,text/plain",".csv") ),tags$hr(),checkboxInput("header","Header",TRUE),# Button downloadButton("downloadData","Download"),actionButton('apply_regex','Apply Regex') ),mainPanel( dataTableOutput("contents") ) ) ) server <- function(input,output) { rv <- reactiveValues() observe({ req(input$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) rv$data <- read.csv(inFile$datapath,header = input$header) }) output$contents <- renderDataTable({ rv$data }) output$downloadData <- downloadHandler( filename = function() { paste("myfile",Sys.Date(),".csv",sep = "") },content = function(file) { write.csv(rv$data,file,row.names = FALSE) } ) observeEvent(input$apply_regex,{ rv$data <- rv$data %>% filter(grepl(regex_to_apply,toupper(close_notes))) }) } shinyApp(ui,server) 。

^(?!^[0-9].*$).*