jQuery篩選數組之grep、each、inArray、map的用法及遍歷json對象

$().ready(
  function(){
    var array = [1,2,3,4,5,6,7,8,9];
    var filterarray = $.grep(array,function(value){
      return value > 5;//筛选出大于5的
    });
    for(var i=0;i<filterarray.length;i++){
      alert(filterarray[i]);
    }
    for (key in filterarray){
      alert(filterarray[key]);
    }
  }
);

$().ready(
  function(){
    var anObject = {one:1,two:2,three:3};//对json数组each
    $.each(anObject,function(name,value) {
      alert(name);
      alert(value);
    });
    var anArray = ['one','two','three'];
    $.each(anArray,function(n,value){
      alert(n);
      alert(value);
    }
    );
  }
);

$().ready(
  function(){
    var anArray = ['one','two','three'];
    var index = $.inArray(‘two',anArray);
    alert(index);//返回该值在数组中的键值，返回1
    alert(anArray[index]);//value is two
  }
);

$().ready(
  function(){
    var strings = ['0','1','2','3','4','S','6'];
    var values = $.map(strings,function(value){
        var result = new Number(value);
        return isNaN(result) ? null:result;//isNaN:is Not a Number的缩写
      }
    );
    for (key in values) {
      alert(values[key]);
    }
  }
);