Powershell计算器脚本无法正常运行

时间:2019-12-16 16:11:20

标签: powershell variables calculation

我创建了一个非常简单的powershell脚本来计算表达式。那就是:

$expression = read-host -prompt "Enter an expression"
$result = $expression
write-host "The result is $result"
read-host

但是,当我像这样使用它时:

  

输入表达式:2 + 3

     

结果是2 + 3

如何使第二行计算结果?

1 个答案:

答案 0 :(得分:2)

也许这对您有帮助:

 $expression = read-host -prompt "Enter an expression"

# check for dangerous code
if( ($expression -replace '^[0-9\+\-\*\/ ]+$').Length -eq 0 ) {
    try {
        $result = Invoke-Expression $expression
        write-host "The result is $result"
    }
    catch {
        write-host "Syntax error"
    }
}
else {
    write-host "Invalid expression"
}