javascript - 使用正则表达式/javascript 提取最后一个单词

Question

这是针对输入线相当短(故意)的用例。当输入已满时，它应该自动发送消息，但保留最后一个单词。

我正在寻找能够满足这些场景的正则表达式:

input: "testing"
output: [1] - "testing"; [2] - null

input: "testing testing"
output: [1] - "testing"; [2] - "testing"

input: "testing testing testing"
output: [1] - "testing testing"; [2] - "testing"

input: "testing testing testing "
output: [1] - "testing testing"; [2] - "testing "

到目前为止，我想出了这些变体:

/(.*)\s+(\w+)/ - closest solution, but doesn't match for one word without spaces
/(.*)(?:\s+(\w+))?/ - is not recognizing last word

我不确定如何满足所有场景。这可能吗？

Answer 1

您可以使用此String#match:

var input = 'testing1 testing2 testing3 ';
var m = input.match(/^(.+?)(?: +(\w+\ *))?$/);
// ["testing1 testing2 testing3 ", "testing1", "testing2 testing3 "]

并在结果数组中使用组 #2 和组 #3。 (使用m[1]和m[2])

Online Regex Demo