在javascript中获取数组映射到对象中的键 - Getting the array mapped to a key in an object in javascript

Getting the array mapped to a key in an object in javascript

如何将数组映射到javascript对象中的特定键?

assignment = {};
assignment.tab = 'assign';
assignment.yrq = 'B343';
assignment.items = [1234,4567];

显示项目作品:

alert(assignment.items); //displays 1234, 4567

但是当我尝试遍历这些项时，我得到了索引号:

for (item in assignment.items) {
    alert(item); //displays 0, then 1
}

错误的for循环对于数组，您应该使用常规的for循环，而不是for-in，这通常用于对象，而不是数组

for (var i=0; i<assignment.items.length; i++) {
    alert( assignment.items[i] );
}

只要改变你的循环使用它作为索引

for (itemIndex in assignment.items) {
    alert(assignment.items[itemIndex]);
}

使用for循环

assignment = {};
assignment.tab = 'assign';
assignment.yrq = 'B343';
assignment.items = [1234,4567];
for(var i = 0; i < assignment.items.length; i++){
    alert(assignment.items[i]);
}

Try

for (item in assignment.items) {
    alert(assignment.items[item]); //displays 1234, then 4567
}