我如何使用javascript数组检查字符串匹配的正则表达式是否已经存在

Question

I am trying to create array of non duplicate line going from end of array to start from another array.

I tried this:

for(var i = len; i > 0; i--){
        if(resultArray[i] != undefined && resultArray[i].match(blahRegex)){
            if(lastArray[blahRegex]){
                console.log("entering here")
                lastArray.push(resultArray[i])
            }
            // console.log(resultArray[i])
        }

Answer 1

You can use filter for that.

Here is an example:

var lastArray = resultArray.filter(value => blahRegex.test(value));

Oh, just noticed that you want to keep only unique values.

var lastArray = resultArray.reduce((acc, value) => {
     if(blahRegex.test(value) && acc.indexOf(value) == -1){
         acc.push(value);
     }
     return acc;
}, []);

What this does is to retain all unique values in the resultArray array that match the blahRegex regex.

Answer 2

您可以结合使用filter和Set ：

let lastArray = [...new Set(resultArray.filter(value => blahRegex.test(value)))];