虽然Shane的回答很好，但对于我的一个项目，我需要自动删除输出消息、警告和安装包。我终于设法得到这个脚本:

InstalledPackage <- function(package) 
{
    available <- suppressMessages(suppressWarnings(sapply(package, require, quietly = TRUE, character.only = TRUE, warn.conflicts = FALSE)))
    missing <- package[!available]
    if (length(missing) > 0) return(FALSE)
    return(TRUE)
}

CRANChoosen <- function()
{
    return(getOption("repos")["CRAN"] != "@CRAN@")
}

UsePackage <- function(package, defaultCRANmirror = "http://cran.at.r-project.org") 
{
    if(!InstalledPackage(package))
    {
        if(!CRANChoosen())
        {       
            chooseCRANmirror()
            if(!CRANChoosen())
            {
                options(repos = c(CRAN = defaultCRANmirror))
            }
        }

        suppressMessages(suppressWarnings(install.packages(package)))
        if(!InstalledPackage(package)) return(FALSE)
    }
    return(TRUE)
}

Use:

libraries <- c("ReadImages", "ggplot2")
for(library in libraries) 
{ 
    if(!UsePackage(library))
    {
        stop("Error!", library)
    }
}

下面是我的代码:

packages <- c("dplyr", "gridBase", "gridExtra")
package_loader <- function(x){
    for (i in 1:length(x)){
        if (!identical((x[i], installed.packages()[x[i],1])){
            install.packages(x[i], dep = TRUE)
        } else {
            require(x[i], character.only = TRUE)
        }
    }
}
package_loader(packages)

非常基本的一个。

pkgs = c("pacman","data.table")
if(length(new.pkgs <- setdiff(pkgs, rownames(installed.packages())))) install.packages(new.pkgs)

 48 lapply_install_and_load <- function (package1, ...)
 49 {
 50     #
 51     # convert arguments to vector
 52     #
 53     packages <- c(package1, ...)
 54     #
 55     # check if loaded and installed
 56     #
 57     loaded        <- packages %in% (.packages())
 58     names(loaded) <- packages
 59     #
 60     installed        <- packages %in% rownames(installed.packages())
 61     names(installed) <- packages
 62     #
 63     # start loop to determine if each package is installed
 64     #
 65     load_it <- function (p, loaded, installed)
 66     {
 67         if (loaded[p])
 68         {
 69             print(paste(p, "loaded"))
 70         }
 71         else
 72         {
 73             print(paste(p, "not loaded"))
 74             if (installed[p])
 75             {
 76                 print(paste(p, "installed"))
 77                 do.call("library", list(p))
 78             }
 79             else
 80             {
 81                 print(paste(p, "not installed"))
 82                 install.packages(p)
 83                 do.call("library", list(p))
 84             }
 85         }
 86     }
 87     #
 88     lapply(packages, load_it, loaded, installed)
 89 }

今天，我偶然发现了rlang包提供的两个方便函数，即is_installed()和check_installed()。

从帮助页面(强调添加):

These functions check that packages are installed with minimal side effects. If installed, the packages will be loaded but not attached. is_installed() doesn't interact with the user. It simply returns TRUE or FALSE depending on whether the packages are installed. In interactive sessions, check_installed() asks the user whether to install missing packages. If the user accepts, the packages are installed [...]. If the session is non interactive or if the user chooses not to install the packages, the current evaluation is aborted.

interactive()
#> [1] FALSE
rlang::is_installed(c("dplyr"))
#> [1] TRUE
rlang::is_installed(c("foobarbaz"))
#> [1] FALSE
rlang::check_installed(c("dplyr"))
rlang::check_installed(c("foobarbaz"))
#> Error:
#> ! The package `foobarbaz` is required.

由reprex包在2022-03-25创建(v2.0.1)

我使用以下将检查包是否安装和依赖项是否更新，然后加载包。

p<-c('ggplot2','Rcpp')
install_package<-function(pack)
{if(!(pack %in% row.names(installed.packages())))
{
  update.packages(ask=F)
  install.packages(pack,dependencies=T)
}
 require(pack,character.only=TRUE)
}
for(pack in p) {install_package(pack)}

completeFun <- function(data, desiredCols) {
  completeVec <- complete.cases(data[, desiredCols])
  return(data[completeVec, ])
}