About $.each in jquery get the use of various return type data

var arr = ["One", "one", "three", "four"];       function () {         alert (this);      });  

The results for each of the above outputs are: One,two,three,four

var arr = ["AAA", "BBB", "CCC" ];       function (i,a) {        alert (i);    // I is the ordinal  of a loop alert (a);  // A is the value

var arr1 = [[1, 4, 3], [4, 6, 6], [7,, 9]]     function(i, item) {        alert (item[0< c6>])  ;

In fact, ARR1 is a two-dimensional array, item is equivalent to taking each one-dimensional array,
Item[0] Relative to the first value in each one-dimensional array
So the above each output is: 1 4 7

var obj = {one:1, two:2, Three:3, Four:4};      function (Key, Val) {         alert (Obj[key]);
    alert (key);   Key
    Alert (val);    Value

The output is: 1 2 3 4

About $.each in jquery get the use of various return type data