JavaScript sorting issues

The sort () method is calculated according to the JavaScript manual, and the result

<script> var arr = [2,3,56,12,546,77,98]; Alert (Arr.sort ());</script>

Based on the JavaScript manual, the sort () method is calculated with the following results:

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Can see that this is not the sort we need, so according to the manual tip:

If you provide a function for the sortfunction parameter, the function must return one of the following values:

• A negative value, if the first argument passed is smaller than the second one.

• 0, if two parameters are equal.

• Positive value if the first argument is larger than the second argument.

So I encapsulate a function demosort ()

<script>    var arr = [2,3,56,12,546,77,98];     Arr.sort (Function demosort (x, y) {        if  (x<  y)  {            return -1;               //less than, returns -1              } else if  (X > y)  {            return 1;                     // Greater than return 1        } else {                     //others, return  0             return 0;        }     });     alert (arr);</script>

In this case, the sort () function is passed again to achieve the correct ordering.

The results are as follows:

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In this way, the real sort is realized. As for reverse order, you can reverse the return value, or use the reverse () function directly.

This article is from the "Hello I am Forest" blog, please make sure to keep this source http://chensenlin.blog.51cto.com/10559465/1862152

JavaScript sorting issues