如何在 RShiny 中进行反应输入？答案

【问题标题】：How to make reactive input in RShiny?如何在 RShiny 中进行反应输入？
【发布时间】：2019-06-08 14:37:44
【问题描述】：

如何为 data.R 代码创建输入值？

例如：

UI.R

numericInput(inputId= "diametro", label= "Diametro do Aco:", value= 0)

服务器.R

????

数据.R

    query <- 
  "select 
cod_ordem_producao as Ordem,
dim_ext_tubo as Diametro,
esp_par_tubo as Parede,
cod_aqa as AQA,
tmo_ciclo_plan as Ciclo,
dth_criacao_reg as Data,
dsc_aco as Grau,

val_lim_escoamento as LE,
val_tensao_residual as TR
from
QT_QTS.PLA_ORDEM_PRODUCAO

where diametro = **_THE INPUT VALUE FOR DIAMETRO HERE_**

order by DTH_CRIACAO_REG desc"

df <- dbGetQuery(
  connection_reportUser,
  query
)
df```

我无法为此创建反应值。用户将在数字小工具中输入“diametro”值，数据库将在数据中搜索。

感谢帮助

【问题讨论】：

标签： r shiny

【解决方案1】：

另一种方法是paste() 函数。如果您需要一个输入向量（多个条件），您可以使用 paste0() 和 collapse 参数来指示用于粘贴向量的每个元素的分隔符。

UI.R

numericInput(inputId= "diametro", label= "Diametro do Aco:", value= 0)

服务器.R

library(RMySQL)
library(shiny)
getQuery <- reactive({
   query <- paste("select cod_ordem_producao as Ordem, dim_ext_tubo as Diametro, esp_par_tubo as Parede, cod_aqa as AQA, tmo_ciclo_plan as Ciclo, dth_criacao_reg as Data, dsc_aco as Grau, val_lim_escoamento as LE, val_tensao_residual as TR from QT_QTS.PLA_ORDEM_PRODUCAO where diametro = ",
   input$diametro,
   " order by DTH_CRIACAO_REG desc",
   sep="")

   df <- dbGetQuery(con, query)
   return(df)
)}

【讨论】：

paste 没有 collapse 参数吗？

【解决方案2】：

你需要这样的东西：

library(shiny)
library(dplyr)
library(glue)

df <- eventReactive(input$diametro,{
  connection_reportUser %>% dbGetQuery(
  glue::glue( "select 
        cod_ordem_producao as Ordem,
        dim_ext_tubo as Diametro,
        esp_par_tubo as Parede,
        cod_aqa as AQA,
        tmo_ciclo_plan as Ciclo,
        dth_criacao_reg as Data,
        dsc_aco as Grau,

        val_lim_escoamento as LE,
        val_tensao_residual as TR
        from
        QT_QTS.PLA_ORDEM_PRODUCAO

        where diametro = {input$diametro}

        order by DTH_CRIACAO_REG desc"
  )
  )
})

【讨论】：