Multiple query filter string

Change class name on click in jQuery

JavaScript

// Array

arrayTest = [];
arrayTest.push( ['product_size', 123] );
arrayTest.push( ['product_size', 456] );
arrayTest.push( ['product_color', 123] );

// Start filter string and array of keys already used

filterString = '';
keysAlreadyUsed = [];

// Loop the array test

$.each( arrayTest, function( index1, value1 ) {

	// If the key has already been set
  
  if( jQuery.inArray( value1[0], keysAlreadyUsed ) ) {
  
  	// Push into the existing array key

  } else {
  
  	// New array we can loop through later with the product_size and the 123, 456 in it.

  }
  
  // Populate filter string
  
  filterString += value1[0] + '=' + value1[1] + '&';
  
  // Push the key already used into the keys already used array
  
  keysAlreadyUsed.push( value1[0] );

});

// Output

console.log(filterString);
console.log(keysAlreadyUsed);