正则表达式匹配句子中的部分单词

Question

I have an input that can receive any string value. The user might type 2 partial words and I need to be able to match the nearest word that matches some of those characters taking into account that when the input value contains a space I need to look in the next word.

The problem that I am having is that for example if I type stack it matches, if I type overflow it matches, if I type stack over it still matches, but if the first word is not complete it does not match.

An example to clarify:

const mySentence = "stack overflow";
let myInput = "sta over"; //input from user

let reg = new RegExp(myInput, 'i');

mySentence.match(reg); //this needs to match mySentence. 

Answer 1

One approach is to prepare your input before creating a RegExp . Since you want to get partial words in the sentence, use the lazy version of the dot star (.*?) to match any possible characters existing before each space.

To do that, simply split the input string by the space and concat with .*?[ ] and then construct the regular expression. Note the blank character [ ] after it, if you want to keep the spaces between words.

 const mySentence = "stack overflow bad but stackoverflow cool"; let myInput = "sta over ba b st coo"; //input from user let reg = new RegExp(myInput.split(" ").join(".*?[ ]"), 'i'); console.log(mySentence.match(reg))

Answer 2

Building on @testing_22, maybe use prepare with "or" (pipe):

 const mySentence = "stack overflow"; let myInput = "sta over ba b st coo"; //input from user var cases = [ "sta over", "stack", "overflow", "stack over", "bob" ]; cases.forEach(item => { let reg = new RegExp(item.split(" ").join("|"), 'gi'); console.log("------------------") console.log("case: " + item) console.log(mySentence.match(reg)) });

results:

------------------
case: sta over
[
    "sta",
    "over"
]
------------------
case: stack
[
    "stack"
]
------------------
case: overflow
[
    "overflow"
]
------------------
case: stack over
[
    "stack",
    "over"
]
------------------
case: bob
null
------------------