我正在尝试模拟setInterval:
var Animator=new (function(){ var jobs={ interval:{} } var self=this; var assignedIntervalNum=0; this.setInterval=function(func,interval){ jobs.interval[assignedIntervalNum]={ func:func, latest:Date.now()-interval, interval:interval }; assignedIntervalNum++; return assignedIntervalNum-1; } this.clearInterval=function(key){ delete jobs.interval[key]; } var requestNextFrame=function(){ var now=Date.now(); for (var key in jobs.interval){ if (jobs.interval[key].latest + jobs.interval[key].interval < now){ jobs.interval[key].func(); jobs.interval[key].latest=now; } } setTimeout(function(){requestNextFrame();},1); } requestNextFrame(); })();但我一直收到错误,指出jobs.interval [key]未定义。 所以我猜删除并没有完全删除该属性,只是将其分配给undefined
对于支持删除对并循环遍历每个对的键/值存储,我有哪些选择?
编辑
我的错!
在函数func()中调用了clearInterval,因此导致错误的行是jobs.interval [key] .latest = now; 在它被删除之后。
所以是的,javascript对象仍然是键/值存储的好选项,它支持删除对并循环遍历每个对
I'm trying to emulate setInterval:
var Animator=new (function(){ var jobs={ interval:{} } var self=this; var assignedIntervalNum=0; this.setInterval=function(func,interval){ jobs.interval[assignedIntervalNum]={ func:func, latest:Date.now()-interval, interval:interval }; assignedIntervalNum++; return assignedIntervalNum-1; } this.clearInterval=function(key){ delete jobs.interval[key]; } var requestNextFrame=function(){ var now=Date.now(); for (var key in jobs.interval){ if (jobs.interval[key].latest + jobs.interval[key].interval < now){ jobs.interval[key].func(); jobs.interval[key].latest=now; } } setTimeout(function(){requestNextFrame();},1); } requestNextFrame(); })();But I keep getting an error stating that jobs.interval[key] is undefined. So i guess delete doesn't exactly remove that property but simply assign it to undefined !?
What are my options for a key/value storage that support removal of pairs and looping through each of them?
EDIT
My bad!
there was a call to clearInterval in the function func(), so the line that was causing the error was jobs.interval[key].latest=now; Just after it's deletion.
So yeah, javascript objects are still good options for a key/value storage that support removal of pairs and looping through each of them
最满意答案
“delete”不会从数组中删除该对象,它会将对象设置为undefined,这就是您收到该错误的原因。
如果要从具有索引i的数组中删除对象,可以使用:
array.splice(i, 1);其中1是要从位置i开始删除的元素数。
如果要通过键从数组“array”中删除一个元素,可以使用:
for (var i=0; i<array.length; i++){ if (array[i]==key){ array.splice(i, 1); break; } }As mentioned in the question, this was a mistake!
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