前情提要

• 在上這節課之前，我們假設你已經有這些能力了：

– 了解App的基本架構(ui.R和server.R)

– 增加控制區參數

– 從網頁上擷取即時資訊

– 將複雜的程式碼打包成一個函數

– 分享你的App至網路上

• 今天的課程我們將會依據步驟完成這些部份：

– 在App中增加新的欄位來選擇醫院屬性

– 在Local端執行排程工作(迴圈 & Sys.sleep())

– 將App設計成讀取Local端檔案來執行

上節課的成果

• 我們以上節課結束時的範例作為開始：

– 請複製下列這串程式碼(這是三軍總醫院的)：

TSGH = function() {
  URL1 = "http://www1.ndmctsgh.edu.tw/ErOnlineNews/ErOnLineData.aspx"
  txt1 = scan(URL1, what="character", encoding="UTF-8")
  txt1_new = paste(txt1, sep="", collapse=" ")
  
  #The result matrix
  Result=matrix(NA,nrow=1,ncol=5)
  rownames(Result)="三軍總醫院"
  colnames(Result)=c("滿床","看診","推床","住院","加護病床")
  
  #The first value
  code.1_1 = "<span id=\"Label7\"><font color=\"Red\">"
  code.1_2 = "</font></span> </td> </tr> <tr> <td> <span id=\"Label3\"><font color=\"Blue\">"
  start.1 = regexpr(code.1_1, txt1_new)
  end.1 = regexpr(code.1_2, txt1_new)
  position.1_1 = start.1[1] + attr(start.1,"match.length")
  position.1_2 = end.1[1] - 1
  Result[1,1]=substr(txt1_new, position.1_1, position.1_2)
  
  #The second value
  code.2_1 = "<span id=\"Label8\"><font color=\"Red\">"
  code.2_2 = "</font></span> </td> </tr> <tr> <td> <span id=\"Label4\"><font color=\"Blue\">"
  start.2 = regexpr(code.2_1, txt1_new)
  end.2 = regexpr(code.2_2, txt1_new)
  position.2_1 = start.2[1] + attr(start.2,"match.length")
  position.2_2 = end.2[1] - 1
  Result[1,2]=substr(txt1_new, position.2_1, position.2_2)
  
  #The third value
  code.3_1 = "<span id=\"Label9\"><font color=\"Red\">"
  code.3_2 = "</font></span> </td> </tr> <tr> <td> <span id=\"Label5\"><font color=\"Blue\">"
  start.3 = regexpr(code.3_1, txt1_new)
  end.3 = regexpr(code.3_2, txt1_new)
  position.3_1 = start.3[1] + attr(start.3,"match.length")
  position.3_2 = end.3[1] - 1
  Result[1,3]=substr(txt1_new, position.3_1, position.3_2)
  
  #The forth value
  code.4_1 = "<span id=\"Label10\"><font color=\"Red\">"
  code.4_2 = "</font></span> </td> </tr> <tr> <td> <span id=\"Label6\"><font color=\"Blue\">"
  start.4 = regexpr(code.4_1, txt1_new)
  end.4 = regexpr(code.4_2, txt1_new)
  position.4_1 = start.4[1] + attr(start.4,"match.length")
  position.4_2 = end.4[1] - 1
  Result[1,4]=substr(txt1_new, position.4_1, position.4_2)
  
  #The fifth value
  code.5_1 = "<span id=\"Label11\"><font color=\"Red\">"
  code.5_2 = "</font></span> </td> </tr> </table> </div> </form> </body> </html>"
  start.5 = regexpr(code.5_1, txt1_new)
  end.5 = regexpr(code.5_2, txt1_new)
  position.5_1 = start.5[1] + attr(start.5,"match.length")
  position.5_2 = end.5[1] - 1
  Result[1,5]=substr(txt1_new, position.5_1, position.5_2)
  
  #print the output
  return(Result)
}

TSGH()

• 如果可以的話，請先把自己的作業包裝成一個函數！

增加不同語言的選項在我們的函數內

• 剛剛我們的函數沒有任何可以選擇的功能，我們應該讓使用者能選擇他希望看英文還中文

TSGH = function(language="English") {
URL1 = "http://www1.ndmctsgh.edu.tw/ErOnlineNews/ErOnLineData.aspx"
txt1 = scan(URL1, what="character", encoding="UTF-8")
txt1_new = paste(txt1, sep="", collapse=" ")

#The result matrix
Result=matrix(NA,nrow=1,ncol=5)
if (language=="English") {
  rownames(Result)="TSGH"
  colnames(Result)=c("Bed status","Waiting for examination","Waiting for bed","Wiating for hospitalize","Waiting for ICU")
}
if (language=="Chinese") {
  rownames(Result)="三軍總醫院"
  colnames(Result)=c("滿床","看診","推床","住院","加護病床")
}

#The first value
code.1_1 = "<span id=\"Label7\"><font color=\"Red\">"
code.1_2 = "</font></span> </td> </tr> <tr> <td> <span id=\"Label3\"><font color=\"Blue\">"
start.1 = regexpr(code.1_1, txt1_new)
end.1 = regexpr(code.1_2, txt1_new)
position.1_1 = start.1[1] + attr(start.1,"match.length")
position.1_2 = end.1[1] - 1
status=substr(txt1_new, position.1_1, position.1_2)

if (language=="English") {
if (status=="是") {Result[1,1]="full"}
if (status=="否") {Result[1,1]="empty"}
}
if (language=="Chinese") {
if (status=="是") {Result[1,1]="是"}
if (status=="否") {Result[1,1]="否"}
}

#The second value
code.2_1 = "<span id=\"Label8\"><font color=\"Red\">"
code.2_2 = "</font></span> </td> </tr> <tr> <td> <span id=\"Label4\"><font color=\"Blue\">"
start.2 = regexpr(code.2_1, txt1_new)
end.2 = regexpr(code.2_2, txt1_new)
position.2_1 = start.2[1] + attr(start.2,"match.length")
position.2_2 = end.2[1] - 1
Result[1,2]=substr(txt1_new, position.2_1, position.2_2)

#The third value
code.3_1 = "<span id=\"Label9\"><font color=\"Red\">"
code.3_2 = "</font></span> </td> </tr> <tr> <td> <span id=\"Label5\"><font color=\"Blue\">"
start.3 = regexpr(code.3_1, txt1_new)
end.3 = regexpr(code.3_2, txt1_new)
position.3_1 = start.3[1] + attr(start.3,"match.length")
position.3_2 = end.3[1] - 1
Result[1,3]=substr(txt1_new, position.3_1, position.3_2)

#The forth value
code.4_1 = "<span id=\"Label10\"><font color=\"Red\">"
code.4_2 = "</font></span> </td> </tr> <tr> <td> <span id=\"Label6\"><font color=\"Blue\">"
start.4 = regexpr(code.4_1, txt1_new)
end.4 = regexpr(code.4_2, txt1_new)
position.4_1 = start.4[1] + attr(start.4,"match.length")
position.4_2 = end.4[1] - 1
Result[1,4]=substr(txt1_new, position.4_1, position.4_2)

#The fifth value
code.5_1 = "<span id=\"Label11\"><font color=\"Red\">"
code.5_2 = "</font></span> </td> </tr> </table> </div> </form> </body> </html>"
start.5 = regexpr(code.5_1, txt1_new)
end.5 = regexpr(code.5_2, txt1_new)
position.5_1 = start.5[1] + attr(start.5,"match.length")
position.5_2 = end.5[1] - 1
Result[1,5]=substr(txt1_new, position.5_1, position.5_2)

#print the output
return(Result)
}

TSGH()
TSGH(language="English")
TSGH(language="Chinese")

練習1

• 請讓你的醫院可以選擇英文或中文輸出

– 下面這個例子是雙和醫院的程式碼

TMUSH = function(language="English") {
  URL2 = "http://eng.shh.org.tw/ER_WEB/ER_WEB/Default.aspx"
  txt2 = scan(URL2, what="character", encoding="UTF-8")
  txt2_new = paste(txt2, sep="", collapse=" ")
  
  #The result matrix
  Result=matrix(NA,nrow=1,ncol=5)
  if (language=="English") {
    rownames(Result)="TMUSH"
    colnames(Result)=c("Bed status","Waiting for examination","Waiting for bed","Wiating for hospitalize","Waiting for ICU")
  }
  if (language=="Chinese") {
    rownames(Result)="雙和醫院"
    colnames(Result)=c("滿床","看診","推床","住院","加護病床")
  }
    
  #The first value
  code.1_1 = "119滿載</td> <td class=\"style1\"> <span id=\"off\"><b><font color=\"Red\">"
  code.1_2 = "</font></b></span> </td> </tr> <tr> <td class=\"style3\"> 等待看診人數"
  start.1 = regexpr(code.1_1, txt2_new)
  end.1 = regexpr(code.1_2, txt2_new)
  position.1_1 = start.1[1] + attr(start.1,"match.length")
  position.1_2 = end.1[1] - 1
  status=substr(txt2_new, position.1_1, position.1_2)
  
  if (language=="English") {
    if (status=="未滿載") {Result[1,1]="empty"}
    if (status=="滿載") {Result[1,1]="full"}
  }
  if (language=="Chinese") {
    if (status=="未滿載") {Result[1,1]="否"}
    if (status=="滿載") {Result[1,1]="是"}
  }
  
  #The second value
  code.2_1 = "等待看診人數 </td> <td class=\"style1\"> <span id=\"Label1\">"
  code.2_2 = "</span> </td> </tr> <tr> <td class=\"style4\"> 等待推床人數"
  start.2 = regexpr(code.2_1, txt2_new)
  end.2 = regexpr(code.2_2, txt2_new)
  position.2_1 = start.2[1] + attr(start.2,"match.length")
  position.2_2 = end.2[1] - 1
  Result[1,2]=substr(txt2_new, position.2_1, position.2_2)
  
  #The third value
  code.3_1 = "等待推床人數</td> <td> <span id=\"Label2\">"
  code.3_2 = "</span> </td> </tr> <tr> <td class=\"style4\"> 等待住院人數"
  start.3 = regexpr(code.3_1, txt2_new)
  end.3 = regexpr(code.3_2, txt2_new)
  position.3_1 = start.3[1] + attr(start.3,"match.length")
  position.3_2 = end.3[1] - 1
  Result[1,3]=substr(txt2_new, position.3_1, position.3_2)
  
  #The forth value
  code.4_1 = "等待住院人數</td> <td> <span id=\"Label3\">"
  code.4_2 = "</span> </td> </tr> <tr> <td class=\"style4\"> 等待加護人數"
  start.4 = regexpr(code.4_1, txt2_new)
  end.4 = regexpr(code.4_2, txt2_new)
  position.4_1 = start.4[1] + attr(start.4,"match.length")
  position.4_2 = end.4[1] - 1
  Result[1,4]=substr(txt2_new, position.4_1, position.4_2)
  
  #The fifth value
  code.5_1 = "等待加護人數</td> <td> <span id=\"Label4\">"
  code.5_2 = "</span> </td> </tr> </table> <br /> 最後更新"
  start.5 = regexpr(code.5_1, txt2_new)
  end.5 = regexpr(code.5_2, txt2_new)
  position.5_1 = start.5[1] + attr(start.5,"match.length")
  position.5_2 = end.5[1] - 1
  Result[1,5]=substr(txt2_new, position.5_1, position.5_2)
  
  #print the output
  return(Result)
}

TMUSH()
TMUSH(language="English")
TMUSH(language="Chinese")

合併檔案並增加欄位

• 根據上節課所學到的，我們應該已經會合併兩個醫院的程式碼：

Result1=TSGH()
Result2=TMUSH()

Final=rbind(Result1,Result2)
Final

• 這時候，我們可能會想要新增一個欄位給使用者選擇，看他想要看台北市的醫院或是新北市的醫院：

Area=c("Taipei","New Taipei")
Final=data.frame(Final)
Final[Area=="Taipei",]
Final[Area=="New Taipei",]

• 至此為止，我們就可以開始寫一個新的App了！

在App中增加新的欄位來選擇醫院屬性

• 我們可以開一個新的R script檔案在我們的App資料夾中，然後把它命名為global.R

– global.R

TMUSH = function(language="English") {
  URL2 = "http://eng.shh.org.tw/ER_WEB/ER_WEB/Default.aspx"
  txt2 = scan(URL2, what="character", encoding="UTF-8")
  txt2_new = paste(txt2, sep="", collapse=" ")
  
  #The result matrix
  Result=matrix(NA,nrow=1,ncol=5)
  if (language=="English") {
    rownames(Result)="TMUSH"
    colnames(Result)=c("Bed status","Waiting for examination","Waiting for bed","Wiating for hospitalize","Waiting for ICU")
  }
  if (language=="Chinese") {
    rownames(Result)="雙和醫院"
    colnames(Result)=c("滿床","看診","推床","住院","加護病床")
  }
  
  #The first value
  code.1_1 = "119滿載</td> <td class=\"style1\"> <span id=\"off\"><b><font color=\"Red\">"
  code.1_2 = "</font></b></span> </td> </tr> <tr> <td class=\"style3\"> 等待看診人數"
  start.1 = regexpr(code.1_1, txt2_new)
  end.1 = regexpr(code.1_2, txt2_new)
  position.1_1 = start.1[1] + attr(start.1,"match.length")
  position.1_2 = end.1[1] - 1
  status=substr(txt2_new, position.1_1, position.1_2)
  
  if (language=="English") {
    if (status=="未滿載") {Result[1,1]="empty"}
    if (status=="滿載") {Result[1,1]="full"}
  }
  if (language=="Chinese") {
    if (status=="未滿載") {Result[1,1]="否"}
    if (status=="滿載") {Result[1,1]="是"}
  }
  
  #The second value
  code.2_1 = "等待看診人數 </td> <td class=\"style1\"> <span id=\"Label1\">"
  code.2_2 = "</span> </td> </tr> <tr> <td class=\"style4\"> 等待推床人數"
  start.2 = regexpr(code.2_1, txt2_new)
  end.2 = regexpr(code.2_2, txt2_new)
  position.2_1 = start.2[1] + attr(start.2,"match.length")
  position.2_2 = end.2[1] - 1
  Result[1,2]=substr(txt2_new, position.2_1, position.2_2)
  
  #The third value
  code.3_1 = "等待推床人數</td> <td> <span id=\"Label2\">"
  code.3_2 = "</span> </td> </tr> <tr> <td class=\"style4\"> 等待住院人數"
  start.3 = regexpr(code.3_1, txt2_new)
  end.3 = regexpr(code.3_2, txt2_new)
  position.3_1 = start.3[1] + attr(start.3,"match.length")
  position.3_2 = end.3[1] - 1
  Result[1,3]=substr(txt2_new, position.3_1, position.3_2)
  
  #The forth value
  code.4_1 = "等待住院人數</td> <td> <span id=\"Label3\">"
  code.4_2 = "</span> </td> </tr> <tr> <td class=\"style4\"> 等待加護人數"
  start.4 = regexpr(code.4_1, txt2_new)
  end.4 = regexpr(code.4_2, txt2_new)
  position.4_1 = start.4[1] + attr(start.4,"match.length")
  position.4_2 = end.4[1] - 1
  Result[1,4]=substr(txt2_new, position.4_1, position.4_2)
  
  #The fifth value
  code.5_1 = "等待加護人數</td> <td> <span id=\"Label4\">"
  code.5_2 = "</span> </td> </tr> </table> <br /> 最後更新"
  start.5 = regexpr(code.5_1, txt2_new)
  end.5 = regexpr(code.5_2, txt2_new)
  position.5_1 = start.5[1] + attr(start.5,"match.length")
  position.5_2 = end.5[1] - 1
  Result[1,5]=substr(txt2_new, position.5_1, position.5_2)
  
  #print the output
  return(Result)
}

TSGH = function(language="English") {
  URL1 = "http://www1.ndmctsgh.edu.tw/ErOnlineNews/ErOnLineData.aspx"
  txt1 = scan(URL1, what="character", encoding="UTF-8")
  txt1_new = paste(txt1, sep="", collapse=" ")
  
  #The result matrix
  Result=matrix(NA,nrow=1,ncol=5)
  if (language=="English") {
    rownames(Result)="TSGH"
    colnames(Result)=c("Bed status","Waiting for examination","Waiting for bed","Wiating for hospitalize","Waiting for ICU")
  }
  if (language=="Chinese") {
    rownames(Result)="三軍總醫院"
    colnames(Result)=c("滿床","看診","推床","住院","加護病床")
  }
  
  #The first value
  code.1_1 = "<span id=\"Label7\"><font color=\"Red\">"
  code.1_2 = "</font></span> </td> </tr> <tr> <td> <span id=\"Label3\"><font color=\"Blue\">"
  start.1 = regexpr(code.1_1, txt1_new)
  end.1 = regexpr(code.1_2, txt1_new)
  position.1_1 = start.1[1] + attr(start.1,"match.length")
  position.1_2 = end.1[1] - 1
  status=substr(txt1_new, position.1_1, position.1_2)
  
  if (language=="English") {
    if (status=="是") {Result[1,1]="full"}
    if (status=="否") {Result[1,1]="empty"}
  }
  if (language=="Chinese") {
    if (status=="是") {Result[1,1]="是"}
    if (status=="否") {Result[1,1]="否"}
  }
  
  #The second value
  code.2_1 = "<span id=\"Label8\"><font color=\"Red\">"
  code.2_2 = "</font></span> </td> </tr> <tr> <td> <span id=\"Label4\"><font color=\"Blue\">"
  start.2 = regexpr(code.2_1, txt1_new)
  end.2 = regexpr(code.2_2, txt1_new)
  position.2_1 = start.2[1] + attr(start.2,"match.length")
  position.2_2 = end.2[1] - 1
  Result[1,2]=substr(txt1_new, position.2_1, position.2_2)
  
  #The third value
  code.3_1 = "<span id=\"Label9\"><font color=\"Red\">"
  code.3_2 = "</font></span> </td> </tr> <tr> <td> <span id=\"Label5\"><font color=\"Blue\">"
  start.3 = regexpr(code.3_1, txt1_new)
  end.3 = regexpr(code.3_2, txt1_new)
  position.3_1 = start.3[1] + attr(start.3,"match.length")
  position.3_2 = end.3[1] - 1
  Result[1,3]=substr(txt1_new, position.3_1, position.3_2)
  
  #The forth value
  code.4_1 = "<span id=\"Label10\"><font color=\"Red\">"
  code.4_2 = "</font></span> </td> </tr> <tr> <td> <span id=\"Label6\"><font color=\"Blue\">"
  start.4 = regexpr(code.4_1, txt1_new)
  end.4 = regexpr(code.4_2, txt1_new)
  position.4_1 = start.4[1] + attr(start.4,"match.length")
  position.4_2 = end.4[1] - 1
  Result[1,4]=substr(txt1_new, position.4_1, position.4_2)
  
  #The fifth value
  code.5_1 = "<span id=\"Label11\"><font color=\"Red\">"
  code.5_2 = "</font></span> </td> </tr> </table> </div> </form> </body> </html>"
  start.5 = regexpr(code.5_1, txt1_new)
  end.5 = regexpr(code.5_2, txt1_new)
  position.5_1 = start.5[1] + attr(start.5,"match.length")
  position.5_2 = end.5[1] - 1
  Result[1,5]=substr(txt1_new, position.5_1, position.5_2)
  
  #print the output
  return(Result)
}

在App中增加新的欄位來選擇醫院屬性-續

• 接著就是基本的ui.R以及server.R。

– ui.R

library(shiny)

# Define UI for ER imformation 
shinyUI(pageWithSidebar(
  
  # Application title
  headerPanel("ER imformation"),
  
  # Selected the hospitals
  sidebarPanel(
    radioButtons("language", h3("Selected the language"), c("English" = "English","中文" = "Chinese")),
    conditionalPanel(condition="input.language=='English'",
      radioButtons("focus1", h3("Do you want to focus a city?"), c("Yes" = "yes", "No" = "no")),
      conditionalPanel(condition="input.focus1=='yes'",                    
        radioButtons("city1", h3("Selected the focused city"), c("Taipei" = "Taipei", "New Taipei" = "New Taipei"))
      )
    ),
    conditionalPanel(condition="input.language=='Chinese'",
      radioButtons("focus2", h3("你只想看一個城市嗎?"), c("是" = "yes", "否" = "no")),
      conditionalPanel(condition="input.focus2=='yes'",                    
        radioButtons("city2", h3("請選擇你想看的城市"), c("台北市" = "Taipei", "新北市" = "New Taipei"))
      )
    )    
  ),
  
  # Show a table including user selection
  mainPanel(
    tableOutput("Final")
  )
))

– server.R

library(shiny)

# Define server logic required to generate and plot a random distribution
shinyServer(function(input, output) {
  
  output$Final =  renderTable({      
    Result=rbind(TSGH(language=input$language),TMUSH(language=input$language))
    Result=data.frame(Result)
    Area=c("Taipei","New Taipei")
    if (input$language=="English"&input$focus1=="yes") {
      return(Result[Area==input$city1,])
    }
    if (input$language=="Chinese"&input$focus2=="yes") {
      return(Result[Area==input$city2,])      
    }
    if (input$language=="English"&input$focus1=="no") {return(Result)}
    if (input$language=="Chinese"&input$focus2=="no") {return(Result)}
  })
  
})

練習2

• 請學習上述程式碼的意義，並加入自己的醫院！

– 可以的話，先上傳目前的成果到網路上！

在Local端執行排程工作

• 寫完App之後，你可能會發現一個問題

– 那就是當醫院一多起來，App的運算速度就變慢許多

• 解決這個問題的方法只有可能是架設一個server，讓他定時掃描各醫院的資料，存檔後讓使用者去讀取那個檔案

– 因此，我們要學會兩個功能(迴圈 & Sys.sleep())

基本函數介紹

• 還記得怎樣合併剛剛的檔案？

Result1=TSGH()
Result2=TMUSH()

Final=rbind(Result1,Result2)
Final

• 有個指令可以幫助我們把這個結果儲存到電腦(存成.csv檔案)

– 請試著將1改成其他數字

filenames=paste("d:/Final",1,".csv",sep="")
write.csv(Final,"d:/Final.csv")

• 有個指令可以讓系統休息，這個指令可以幫助我們定時做一些事情

Sys.sleep(5) # 讓系統休息5秒

• 迴圈功能令可以讓電腦重複做一些一樣的事情，讓它結合上面的函數，就可以定時做一些事情

– 我們結合上述幾個程式碼讓他每隔3秒就存一個新檔案，連續儲存5次

for (i in 1:5) {
Sys.sleep(3)
filenames=paste("d:/Final",i,".csv",sep="")
write.csv(Final,filenames)
}

練習3

• 除了定時將檔案寫出去以外，你有沒有可能想到一個方法，將迴圈功能包含下列事項：

1. 剛剛的指令只是讓他“每隔一段時間就寫出一次檔案”，能否改成“每隔一段時間就掃描一次，並且寫出檔案”

2. 考慮到未來我們要使用App來讀檔，我們必須寫出2個檔案，1個是歷史紀錄，另1個是每次使用者訪問時都必須讀的檔案？

3. 可否同時有中文&英文的輸出？

將App設計成讀取Local端檔案來執行

• 我們假設在剛剛的練習中，我們可以輸出兩個即時檔，中文檔名叫做Final_Chinese.csv，英文檔名叫做Final_English.csv

• 這時候我們可以改變一下剛剛的App，在server.R的部份請他使用讀檔資料

– ui.R(不變)

library(shiny)

# Define UI for ER imformation 
shinyUI(pageWithSidebar(
  
  # Application title
  headerPanel("ER imformation"),
  
  # Selected the hospitals
  sidebarPanel(
    radioButtons("language", h3("Selected the language"), c("English" = "English","中文" = "Chinese")),
    conditionalPanel(condition="input.language=='English'",
      radioButtons("focus1", h3("Do you want to focus a city?"), c("Yes" = "yes", "No" = "no")),
      conditionalPanel(condition="input.focus1=='yes'",                    
        radioButtons("city1", h3("Selected the focused city"), c("Taipei" = "Taipei", "New Taipei" = "New Taipei"))
      )
    ),
    conditionalPanel(condition="input.language=='Chinese'",
      radioButtons("focus2", h3("你只想看一個城市嗎?"), c("是" = "yes", "否" = "no")),
      conditionalPanel(condition="input.focus2=='yes'",                    
        radioButtons("city2", h3("請選擇你想看的城市"), c("台北市" = "Taipei", "新北市" = "New Taipei"))
      )
    )    
  ),
  
  # Show a table including user selection
  mainPanel(
    tableOutput("Final")
  )
))

– server.R

library(shiny)

# Define server logic required to generate and plot a random distribution
shinyServer(function(input, output) {
  
  output$Final =  renderTable({      
    Result1=read.csv("d:/Final_English.csv",row.names=1)
    Result2=read.csv("d:/Final_Chinese.csv",row.names=1)
    Area=c("Taipei","New Taipei")
    if (input$language=="English"&input$focus1=="yes") {
      return(Result1[Area==input$city1,])
    }
    if (input$language=="Chinese"&input$focus2=="yes") {
      return(Result2[Area==input$city2,])      
    }
    if (input$language=="English"&input$focus1=="no") {return(Result1)}
    if (input$language=="Chinese"&input$focus2=="no") {return(Result2)}
  })
  
})

• 透過這樣的設計，我們就可以在第一個R program裡面請他定時掃描並寫出檔案，而在第二個R program裡面請他開啟App，讓使用者能輕鬆取得即時資訊。

練習4

• 請利用upload資料夾當作儲存空間，並完成下面事情：

1. 找某一台台電腦負責定時掃瞄網頁，並且儲存檔案至upload資料夾內

2. 找另一台電腦寫出App，令他隨時讀取upload資料夾內的資訊

持續學習

• 在這兩堂課程內，你們已經學會了基本的WebApp撰寫方法，我希望這能夠激起你們的興趣，如果你需要更高階的應用，可以參考Shiny的官方網站：