javascript文本匹配计数和正则表达式空格不起作用

Question

我有一个问题。 我会为文本匹配续和排序匹配计数生成一个小技巧。 单击以查看jsfiddle实时示例

我的示例脚本：

var testtext1 = "apple banana and kiwi pineapple juice";
var testtext2 = "need apple banana pineapple milkshake";
var testtext3 = "apple pineapple lower prices";
var testtext4 = "only apple banana kiwi pineapple lovers";
var testtext5 = "kiwi pineapple apple banana sales";

alert(testtext1.match(/apple banana kiwi|apple banana|apple|banana|kiwi/gi).length); //3 matches
alert(testtext2.match(/apple banana kiwi|apple banana|apple|banana|kiwi/gi).length); //2 m
alert(testtext3.match(/apple banana kiwi|apple banana|apple|banana|kiwi/gi).length); //2 m
alert(testtext4.match(/apple banana kiwi|apple banana|apple|banana|kiwi/gi).length); //2 m
alert(testtext5.match(/apple banana kiwi|apple banana|apple|banana|kiwi/gi).length); //3 matches

text1 =只匹配3个为什么？ 观看正则表达式

苹果香蕉猕猴桃或苹果香蕉或苹果或香蕉或猕猴桃

苹果香蕉奇异果不匹配0

苹果香蕉YES Match 1

正确的是匹配2

香蕉YES 3

奇异果YES 4

好吧，为什么返回3个匹配项而不是4个匹配项？ 还有其他例子吗？

Answer 1

看看下面的演示

现场演示

用单词边界将其包围，否则pineapple将与apple匹配

\b(apple banana kiwi|apple banana|apple|banana|kiwi)\b

火柴

apple banana and kiwi pineapple juice        2
need apple banana pineapple milkshake        1
apple pineapple lower prices                 1
only apple banana kiwi pineapple lovers      1
kiwi pineapple apple banana sales            2

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编辑

如果您更改订单，则结果将有所不同

\b(apple|banana|apple banana kiwi|apple banana|kiwi)\b

现场演示

apple banana and kiwi pineapple juice        3