ArrayList<String> to CharSequence[]
What would be the easiest way to make a CharSequence[]
out of ArrayList<String>
?
Sure I could iterate through every Array开发者_开发问答List
item and copy to CharSequence
array, but maybe there is better/faster way?
You can use List#toArray(T[])
for this.
CharSequence[] cs = list.toArray(new CharSequence[list.size()]);
Here's a little demo:
List<String> list = Arrays.asList("foo", "bar", "waa");
CharSequence[] cs = list.toArray(new CharSequence[list.size()]);
System.out.println(Arrays.toString(cs)); // [foo, bar, waa]
Given that type String
already implements CharSequence
, this conversion is as simple as asking the list to copy itself into a fresh array, which won't actually copy any of the underlying character data. You're just copying references to String
instances around:
final CharSequence[] chars = list.toArray(new CharSequence[list.size()]);
I know this post is 12 years old but I could not find a solution for this in Kotlin. Eventually I figured it out:
Kotlin:
val listOfStrings: List<String> = listOf("Hello,", "World!")
val charSequenceArray: Array<CharSequence> = listOfStrings.toArray(arrayOf<CharSequence>()) //Equivalent type to `CharSequence[]`
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