打印 Javascript 对象中的所有属性
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Printing all properties in a Javascript Object
提问by Rtr Rtr
I am following a code academy tutorial and i am finding this difficult.
我正在学习代码学院教程，我发现这很难。
The assignment is the following:
任务如下：
Use a for-in loop to print out all the properties of nyc.
使用 for-in 循环打印出 nyc 的所有属性。
var nyc = {
fullName: "New York City",
mayor: "Michael Bloomberg",
population: 8000000,
boroughs: 5
};
// write your for-in loop here
for (var in nyc){
console.log(population);
}
回答by lostsource
Your syntax is incorrect. The varkeyword in your forloop must be followed by a variable name, in this case its propName
你的语法不正确。循环中的var关键字for必须后跟变量名，在本例中为propName
var propValue;
for(var propName in nyc) {
propValue = nyc[propName]
console.log(propName,propValue);
}
I suggest you have a look here for some basics:
我建议你看看这里的一些基础知识：
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/for...in
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/for...in
回答by Tomas Nekvinda
What about this:
那这个呢：
var txt="";
var nyc = {
fullName: "New York City",
mayor: "Michael Bloomberg",
population: 8000000,
boroughs: 5
};
for (var x in nyc){
txt += nyc[x];
}
