jsではどのようにhashオブジェクトのキーのペアを取得しますか?

var obj = { '1' : 'apple', '2' : 'orange', '3' : 'pear' };

var arrMsg = ['apple', 'orange', 'pear'];

var array  = [{'111': 'apple'}, {'222': 'orange'}];

for(var key in obj){    
    console.log(key);      //    1  2  3 
    console.log(obj[key]); //    apple orange pear
}

$.each(obj, function(i) {
    alert(i);   	//    1 2 3 
    alert(obj[i]);	//    apple orange pear
});

for(var [key,value] in obj){    
    console.log(key);      //    1 2 3
    console.log(value);    //    undefined undefined undefined
}


//     ，   
for(var (key,value) in obj){    
    console.log(key);      //    1 2 3
    console.log(value);    //    apple orange pear
}

for(var val in arrMsg){     
    console.log(val);        //     0 1 2
}

for(var val in arrMsg){     
    console.log(arrMsg[val]);      //     apple orange pear
}

for(var val in arrMsg){     
    console.log(val);      //     apple orange pear
}