R Shiny : Write looped reactive inputs to textfile

Question

我目前正在开展一个项目，在该项目中，用户向应用程序输入一组用于上传数据集的编辑规则。用户通过 UI 中的文本框输入输入规则。我计划创建一个包含用户设置的编辑规则的文本文件。

现在，我的问题是创建一个代码来创建一个包含这些编辑规则的列表或向量，因为我想不出一种方法将用户的输入插入到代码中。这是我所做的:

textprepGen <- function(x,y,z){
  for(i in 1:x){
    z[[i]] <- paste(y[1], paste("input", 
                                paste("input",i, sep = "_"), sep = "$"), sep = " ") 
  }
  return(z)
}

它不起作用的原因是因为粘贴功能自动将代码设置为字符，所以它不读取输入，input$input_1，input$input_2，...

有什么建议吗？

这是 UI 和服务器:

shinyUI(fluidPage(theme="bootstrap.css",

                  titlePanel("Edit Rules"),

                  sidebarPanel(

                    fileInput('file_upload', 'Upload CSV File',
                              accept=c('text/csv', 
                                       'text/comma-separated-values,text/plain', 
                                       '.csv')),  

                    uiOutput("editrulePanel")

                  ),

                  mainPanel(
                    h4("Data Summary")

                  )
)
)

shinyServer(function(input, output, session) {

  # Text input list assignment in order for the data to show up in UI
  textinpList <-vector("list", 20)

  # Textfile preparation for the lines to be written on the textfile    
  textprepList <- vector(20)

  # Function to generate text inputs
  ## A for loop is used to generate only the columns that are in the data file
  textinpGeneration <- function(x,y,z){
    for(i in 1:x){
      z[[i]] <- list(textInput(paste("text", i, sep = "_"), 
                               label = h5(y[i]), 
                               value = ">= 0"
      )
      )
    }
    return(z)
  }

  textprepGen <- function(x,y,z){
    for(i in 1:x){
      z[[i]] <- paste(y[1], paste("input", 
                                  paste("input",i, sep = "_"), sep = "$"), sep = " ") 
    }
    return(z)
  }


  # Dynamic UI
  output$editrulePanel <- renderUI ({
    # Assigns the input of the uploaded data to a variable

    inFile <- input$file_upload

    # If no file is uploaded, no table will be displayed in the main panel

    if (is.null(inFile))
      return(NULL)

    # Read csv file uploaded

    dataFile <- read.csv(inFile$datapath)

    # Count the number of columns of the data file and assign to a variable
    ## This is used to know the number of options 
    ## to show in the editrule panel

    dataCol <- as.numeric(ncol(dataFile))

    # Read the column names and assign to a variable

    datacolName <- colnames(dataFile)

    textprepGen(dataCol, datacolName, textprepList)

    # Conditional panel for editrules show if a file has been uploaded

    conditionalPanel(condition = "is.null(inFile) == FALSE",
                     h4("Please input edit rule"),
                     textinpGeneration(dataCol,datacolName,textinpList)
    )

  })

  # Preparation for writing a textfile
  editruleFile <- file("editrules.txt")
  writeLines(c(textprepList), editruleFile)
  close(editruleFile)


})

我想要实现的结果文本文件:

# numerical rules
RECOV <= 0
PAID >= 0
CASE >= 0
INC >= 0

只有逻辑符号和数字是用户输入的。

Answer 1

无论如何，非常感谢 Eugene Choe。刚刚让我的代码工作。还想出了将其正确写入文本文件的方法。

这是输入的最终代码:

for(i in 1:addruleNumber){
                                              textprepList[i+1+dataCol] <- list(paste(
                                                eval(parse(text =  paste("input", 
                                                                         paste("lhand",i,sep="_"), 
                                                                         sep = "$"))),
                                                eval(parse(text =  paste("input", 
                                                                         paste("logexp",i,sep="_"), 
                                                                         sep = "$"))),
                                                eval(parse(text =  paste("input", 
                                                                         paste("rhand",i,sep="_"), 
                                                                         sep = "$"))),
                                                sep = " "))
                                            }

这是我修复文本文件输出的方法:

textprepList[1] <- "# numerical rules"  
                                          for(i in 1:dataCol){
                                            textprepList[i+1] <- list(paste(datacolName[i],
                                                                            eval(parse(text =  paste("input", 
                                                                                                     paste("text",i,sep="_"), 
                                                                                                     sep = "$"))), sep = " "))
                                          }