Introduction to copying json objects (arrays and objects) in jQuery)

1. $. map method provided by jQuery
Copy codeThe Code is as follows:
$. Map (json, function (n) {return n ;});

This method was used to copy an array. Today, we use it to copy a record in the array. We found that the field name is lost, and then we found the second method.
2. Deep replication and light Replication
Copy codeThe Code is as follows:
// Perform shallow copy (only copy the top-level non-object elements)
Var newObject = jQuery. extend ({}, oldObject );
// Deep replication (one layer to the bottom)
Var newObject = jQuery. extend (true, {}, oldObject );

The deep replication method is used. When copying an object, it is found that the field is lost.
3. Filter Arrays
I found the method of javascript array, but there was no filtering method. Later I found jQuery provided. I tried it and it was very useful.
Copy codeThe Code is as follows:
$. Grep (jsonTmp, function (item)
{
Return item. LegendTitle = field;
}, False );

The function content can be written based on actual needs. If not, refer to jQuery's help, which is very detailed.
4. Sort arrays by the way
Copy codeThe Code is as follows:
Json2.sort (function (a, B) {return a ["requiredColumn"] ["crimeTime"]> B ["requiredColumn"] ["crimeTime"]? 1:-1 });

This is easy to use.