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Walking through an array in IF conditional in Javascript

I am creating a very lightweight search functionality that accepts the following:

if (searchStr == people.first_name ||
    searchStr == people.last_name || 
    searchStr == people.job || 
    searchStr == people.skills.forEach(function(x) { return x })) {
  Results.push(people)
}

searchStr

- search line; "people" is a person object that has one first and last name and job, but only one of those that is an array - people.skills - is there anyway, I can go through this array in if-conditional with anonymous function?

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6 answers


You can use Array.prototype.some

to evaluate whether a condition is true for at least one entry in an array. It is better than Array.prototype.filter

that, because he will leave the first entry early to judge it as true.

if (searchStr == people.first_name ||
    searchStr == people.last_name || 
    searchStr == people.job || 
    people.skills.some(function(x) { return searchStr == x })) {
  Results.push(people)
}

Array.prototype.some

is new in Ecmascript 5 and is fairly well supported now .



You can improve your search by doing a partial search for terms instead of an exact search, toggling comparison comparisons with Array.prototype.indexOf

to see if the string contains the search term.

if (contains(people.first_name, searchStr) ||
    contains(people.last_name, searchStr) || 
    contains(people.job, searchStr) || 
    people.skills.some(function(x) { return contains(x, searchStr); })) {
  Results.push(people)
}

function contains(a, b) {
  return a.indexOf(b) >= 0;
}
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For this purpose is used Array.prototype.some

:

if (searchStr == people.first_name ||
    searchStr == people.last_name || 
    searchStr == people.job || 
    people.skills.some(function(skill) {
      return searchStr == skill;
    })) {
  Results.push(people)
}

But the use of an anonymous function is not necessary in this case. We can use the method Array.prototype.indexOf

:

if (searchStr == people.first_name ||
    searchStr == people.last_name || 
    searchStr == people.job || 
    people.skills.indexOf(searchStr) != -1) {
  Results.push(people)
}


or, more idiomatic:

    people.skills.indexOf(searchStr)+1

Keep in mind that Array.prototype.every

, some

, forEach

, filter

, reduce

and reduceRight

are part of the ECMAScript 5 and are therefore not supported in older browsers that only support ECMAScript <= 3.1. You should use a polyfill if that's the problem.

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You can use indexOf to determine if a value exists in an array using javascript if you really need to step through the array and then use some function like @DanielImms recommend.

if (searchStr == people.first_name ||
    searchStr == people.last_name || 
    searchStr == people.job || 
    people.skills.indexOf(searchStr)>-1) {
  Results.push(people)
}
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Another option is using Array.reduce()

that returns a single value.

Try the following:

if (searchStr == people.first_name ||
    searchStr == people.last_name || 
    searchStr == people.job || 
    people.skills.reduce(function(p,c) {
       return p || (searchStr == c);
      },false)
}
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var searchSkills = [].concat.apply([], people.skills);

if (searchStr == people.first_name ||
    searchStr == people.last_name || 
    searchStr == people.job || 
    searchSkills.indexOf(searchStr) >= 0 {
  Results.push(people)
}

I'll leave this for posterity, but this method will probably be useful if people.skills

multidimensional.

As a side note, I would suggest that it is indexOf

much more efficient than doing filter

map

or some

.

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And for the sake of thoroughness, if you were at the forefront and with Ecmascript 7, you could use Array.prototype.includes() 

if (searchStr == people.first_name ||
    searchStr == people.last_name || 
    searchStr == people.job || 
    people.skills.includes(searchStr)
)
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