ArrayList - 如何检查索引是否存在? [英] ArrayList - how can I check if an index exists?

问题描述

我正在使用 ArrayList 并在特定索引处添加数据，如何检查特定索引是否存在?

I'm using ArrayList<String> and I add data at specific indices, how can I check if a specific index exists?

我应该简单地get() 并检查值吗?还是我应该等待异常?还有别的办法吗?

Should I simply get() and check the value? Or should I wait for an exception? Is there another way?

更新:感谢您的回答，但因为我只在特定索引处添加内容，列表的长度不会显示哪些可用.

Update: Thank you for your answers, but because I'm only adding stuff at specific indices, the length of the list will not show me which are available.

推荐答案

方法 arrayList.size() 返回列表中的项目数 - 所以如果索引大于或等于 size()，它不存在.

The method arrayList.size() returns the number of items in the list - so if the index is greater than or equal to the size(), it doesn't exist.

if(index >= myList.size()){
  //index not exists
}else{
 // index exists
}

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