Question

我有一个字符串数组，其中包含以字母开头的元素，然后是冒号，然后是一些随机文本。例如：

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我想只保留以a = [ "a:aushdad", "b:ofigjhld", "g:dkfgjdfg", "b:kjfdgkdfj" ]开头的第一个元素，并且对于可能存在的任何其他重复项都是如此。

最终结果应为：

b:

如何实现这一目标？如果您需要更多信息，请与我们联系。

Answer 1

您可以使用Array.reduce：

var a = [
    "a:aushdad",
    "b:ofigjhld",
    "g:dkfgjdfg",
    "b:kjfdgkdfj"
]

var letters = [];
var result = a.reduce(function(prev,current){
  if(letters.indexOf(current[0]) === -1) {
     letters.push(current[0]);
     prev.push(current);
  }
  return prev;
}, []);

console.log(result); // ["a:aushdad", "b:ofigjhld", "g:dkfgjdfg"]

Answer 2

您可以使用数组中的filter。

//store already used 'key'
var map = {};

//regexp used to get the interesting part 
var regexp = /^.*?:/;

//function used for the filter, true add the value to the result array.
function myFilter(value){
    //get the key
    var key = regexp.exec(value)[0];

    //key not null and not used ?
    if(key && !map[key]){
        map[key] = true;
        return true;
    }
    else{
        return false;
    }
}

var result = myArray.filter(myFilter);

当另一个元素以相同的字母开头时，从String Array中删除元素

2 个答案: