<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>循环</title>
</head>
<body>
<script>
// for()
/*var arr=[{},{}];
var result=[];
for(var i=0;i<arr.length;i++){
var obj=arr[i];
result.push({
"id":obj.id,
"requireState":obj.requireState
});
}
console.log(result);*/
// 将一个对象里的部分属性取出来
var arr = [{"id":"8a58bc8f5fbe8049015fbe8851da009c","requireState":"1"}, {"id":"8a58bc8f5fbe8049015fbe8851da009c","requireState":"1"}];
// console.log(arr);
var result = [];
for(var i=0;i<arr.length;i++){
var obj = arr[i];
result.push({
"id":obj.id,
// "requireState":obj.requireState
});
}
console.log(result);
console.log(result[0]);
// while(expression){statement}注意，使用while(true)则会创建一个循环
/*var count=0;
while(count<10){
console.log(count);
count++;
}
*/
//do/while循环体是在循环的底部而不是顶部，这就意味着循环体至少会执行一次
function printArray(a){
var len = a.length;i=0;
if(len == 0){
console.log("Empty Array");
}else{
do{
console.log(a[i]);//2,3,4,1
}while(++i<len);
}
}
var a = [2,3,4,1];
printArray(a);
//for/in for(vaiable in object{statement}
for(var i=0;i<a.length;i++){
console.log(a[i]);//2,3,4,1
}
for(p in a){
console.log(a[p]);//2,3,4,1
}
</script>
</body>
</html>