Is there a JavaScript equivalent to PHP's in_array()?

JavaScript Equivalent to PHP's in_array()

JavaScript does not have an exact equivalent to PHP's in_array() function, which checks if one array contains a specific value from another array. However, several third-party libraries come with utility functions that provide similar functionality.

For Basic Value Comparison

For simple value comparison, you can use one of these libraries:

• jQuery's jQuery.inArray(): Checks if a value exists in an array efficiently.

if ($.inArray('value', array) !== -1) {
  // Value found in the array
}

• Prototype's Array.indexOf(): Returns the index of an array element that matches the specified value.

if (array.indexOf('value') !== -1) {
  // Value found in the array
}

For Array Comparison

If you need to check if one array is contained within another, you can use this custom function:

function inArray(needle, haystack) {
  return haystack.some(function(value) {
    return value.every(function(item) {
      return needle.includes(item);
    });
  });
}

This function implements the behavior of PHP's in_array(), where it returns true if the values of the needle array are all contained within one of the haystack array's subarrays.

Example

var needle = ['p', 'h'];
var haystack = [['p', 'h'], ['p', 'r'], 'o'];

if (inArray(needle, haystack)) {
  // Needle array is contained in one of the subarrays of haystack
}

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