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This article is about what the powerful JavaScript skills are. The editor thinks it is very practical, so share it with you as a reference and follow the editor to have a look.

1. Replace all

We know that the string.replace () function only replaces what happens the first time.

You can replace everything that appears by adding / g to the end of the regular expression.

Var example = "potato potato"; console.log (example.replace (/ pot/, "tom")); / / "tomato potato" console.log (example.replace (/ pot/g, "tom")); / / "tomato tomato"

two。 Extract unique valu

By using the Set object and the expansion operator, we can create a new array with unique values.

Var entries = [1, 2, 2, 3, 4, 5, 6, 6, 7, 7, 8, 4, 2, 1] var unique_entries = [... new Set (entries)]; console.log (unique_entries); / / [1,2,3,4,5,6,7,8]

3. Convert a number to a string

We just need to use the concatenation operator with empty quotation marks.

Var converted_number = 5 + "; console.log (converted_number); / / 5 console.log (typeof converted_number)

4. Convert a string to a number

All we need is the + operator.

Note that it only applies to "string numbers".

The_string = "123"; console.log (+ the_string); / / 123the_string =" hello "; console.log (+ the_string); / / NaN

5. Randomly arranging elements in an array

I do this every day.

Var my_list = [1,2,3,4,5,6,7,8,9]; console.log (my_list.sort (function () {return Math.random ()-0.5})); / / [4,8,2,9,1,3,6,5,7]

6. Flattened multidimensional array

Just use the unfold operator.

Var entries = [1, [2, 5], [6, 7], 9]; var flat_entries = [] .concat (....); / / [1, 2, 5, 6, 7, 9]

7. Shorten conditional statement

Let's look at this example:

If (available) {addToCart ();}

Shorten it by simply using variables and functions:

Available & & addToCart ()

8. Dynamic attribute name

I always thought that an object had to be declared before dynamic properties could be assigned.

Const dynamic = 'flavour'; var item = {name:' Coke', [dynamic]: 'Cherry'} console.log (item); / / {name: "Coke", flavour: "Cherry"}

9. Adjust / empty the array using length

We basically covered the length of the array.

If we want to resize the array:

Var entries = [1,2,3,4,5,6,7]; console.log (entries.length); / / 7 entries.length = 4; console.log (entries.length); / / 4 console.log (entries); / / [1,2,3,4]

If we want to empty the array:

Var entries = [1,2,3,4,5,6,7]; console.log (entries.length); / / 7 entries.length = 0; console.log (entries.length); / / 0 console.log (entries); / / [] Thank you for reading! This is the end of this article on "what are the powerful JavaScript skills?". I hope the above content can be of some help to you, so that you can learn more knowledge. if you think the article is good, you can share it for more people to see!

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