当列表中有多个元素时查找元素的索引

Question

我有一个列表是这样写的：

def availFood = ["${property['Cake']}", "${property['Custard']}", "${property['Donuts']}"]

当我们打印那个列表时，它看起来像这样：

[true, true, false]

我想说的是“对于每个真实值，做一堆事情”。我是这样做的：

for(currentFood in availFood){
    if (currentFood == "true"{

    //Find out the index of the current food to figure out which one it was
    def foodNum = availFood.indexOf(currentFood)
    def foodName = ""
    //a big if statement for 0 = "Cake", 1 = "Custard", 2 = "Donuts"
    println("Our current food is ${foodName}!")

    }
}

但是 .indexOf 将 return 匹配 currentFood 的第一个值的索引，而不是元素 currentFood 的索引。意思是因为索引 1 和 2 都为真，availFood.indexOf(currentFood) 将始终 return 1 这将给我错误的 foodName。

我该如何解决这个问题？

Answer 1

要执行您真正想要的操作，惯用代码可能如下所示：

def property = [ Custard:true, Donuts:true ] // fake out your property

def availFood = [ 'Cake', 'Custard', 'Donuts' ]

availFood.eachWithIndex{ foodName, foodNum ->
  if( !property[ foodName ] ) return
  println "Our current food is $foodName / $foodNum!"
}

打印

Our current food is Custard / 1!
Our current food is Donuts / 2!

当列表中有多个元素时查找元素的索引

Find index of an element when there are multiples of the element in a list

groovy