Change Color In A String Array In Js?

Javascript Assortment

Javascript arrays are ordered lists of information and can hold any blazon of data in each slot.

Arrays in Javascript are dynamically sized, automatically growing.

Arrays tin can be created in two ways.

Array constructor
Array literal notation

Array constructor

The following lawmaking uses the Array constructor.

var colors = new Array();

You tin pass the count into the constructor, and the length property volition gear up to that value.

var colors = new Array(xx);

Y'all can laissez passer items to Array constructor.

var colors = new Array("red", "blue", "green");

It's OK to omit the new operator when using the Array constructor.

          var          colors = Array(3);      //create an          assortment          with three items          var          names = Array("red");   //create an          array          with one item, the string          "reddish"

Array literal

An array literal includes square brackets and a comma-separated list of items.

          var          colors = ["scarlet",          "blueish",          "green"]; //creates an          array          with 3 strings          var          names = [];                        //creates an empty          array

Loop

You can enumerate the content of an array using a for loop.

                                          var                            myArray = [ 100,              "A", true ]; for (                              var                            i = 0; i < myArray.length; i++) {   console.log("Index "              + i +              ": "              + myArray[i]); }

The lawmaking higher up generates the following result.

Array alphabetize

To get and set array values, use square brackets and the zero-based numeric index.

                                          var                            colors = ["red",              "blue",              "green"];       console.log(colors[0]);                      colors[2] =              "new blackness";              //change the third item              colors[3] =              "new brown";              //add a fourth item              console.log(colors.toString());/              /                                                                      w                                          w                                                                      w                                          .              j                                                                      a                                          five                                          a              two                                          s              .                                                                      c                                                                      o                                                                      m                              var                            myArray = new Assortment(); myArray[0] = 100; myArray[one] =              "Adam"; myArray[2] = true; console.log(myArray.toString());

The code in a higher place generates the following issue.

If the alphabetize is less than the number of items in the array, then information technology volition return the value in the getter and replace the value in the setter.

If a value is set to an alphabetize that is beyond the end of the array, the array is expanded.

Assortment length

The number of items in an assortment is stored in the length property.

          var          colors = ["ruddy",          "blue",          "greenish"];    //creates an          assortment          with iii strings          var          names = [];                           //creates an empty          array          panel.log(colors.length);    //3 console.log(names.length);     //0          var          names =          new          Array();  console.log(names.length);//0

The code above generates the following result.

Array length in Javascript is not read-only.

By setting the length property, you can easily remove items from or add items to the end of the array.

                                          var                            colors = ["red",              "bluish",              "dark-green"];              //creates an array with iii strings              colors.length = 2; console.log(colors[2]);              //undefined              console.log(colors.toString());          colors = ["red",              "blue",              "light-green"];              //creates an array with 3 strings              colors.length = 4; console.log(colors[3]);              //undefined              console.log(colors.toString());

The code above generates the following consequence.

Array length Instance 2

Nosotros tin apply length property to add together items the end of an array.

The concluding detail in an array is at position length - 1, then the side by side bachelor open slot is at position length.

                                          var                            colors = ["red",              "blue",              "dark-green"];              //creates an assortment with 3 strings              colors[colors.length] =              "black";              //add a color (position three)              console.log(colors.toString());   colors[colors.length] =              "brownish";              //add some other colour (position 4)              panel.log(colors.toString());

The code to a higher place generates the following consequence.

Assortment length Instance three

                                          var                            colors = ["red",              "blue",              "light-green"];              //creates an assortment with three strings              colors[99] =              "black";              //add a colour (position 99)              console.log(colors.length);              //100

The code above generates the following issue.

Array detecting

We have 2 ways to check if a variable is an array. The first method is to use instanceof operator.

          if          (value          instanceof          Array){    //do          something on the          array          }

The second one is to use Array.isArray() method.

          if          (Array.isArray(value)){  //exercise          something on the          array          }

Array detecting Example

                                          var                            colors = ["A",              "B",              "C"];              //creates an array with 3 strings                            if (Assortment.isArray(colors)){     panel.log("colors is an assortment"); }

The code above generates the following result.