javascript 当Javascript中的数组为空时在数组中添加元素不起作用
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adding element in array when array is empty in Javascript is not working
提问by Vignesh
I am facing a problem in javascript array...i am using Serversent event in JS. I will be getting few values from server frequently...
我在 javascript 数组中遇到问题...我在 JS 中使用 Serversent 事件。我会经常从服务器获取很少的值...
My task is to catch all the details and display in drop-down box...
我的任务是捕获所有详细信息并显示在下拉框中...
Now the problem is, during the first request, i will getting values seperated by comma.. I have array object in js...i will check if the array is empty, if so, then i will include the values in combo...
现在的问题是，在第一个请求期间，我将获取由逗号分隔的值.. 我在 js 中有数组对象...我将检查数组是否为空，如果是，那么我将包含组合中的值.. .
code:
代码：
var varArr = new Array();
//since i am using SSE, i will executing this below part multiple times automaticall when ever server pushes data..
if(!varArr.length){
varArr[0]='somevalue';
//Printing some value in <div>
}
else{
//some task...to print in <div>
}
Since i have added some values in array if the array is empty, i am not getting any values printed in div (//Printing some value in ), instead i am getting (//some task...to print in )
因为如果数组为空，我在数组中添加了一些值，所以我没有在 div 中打印任何值（//打印一些值），而是得到（//一些任务...打印）
回答by Andy
Perhaps you mean to do this?
也许你的意思是这样做？
var varArr = new Array();
if (varArr.length === 0) {
varArr.push(somevalue);
// Printing some value in <div>
} else {
// Some task...to print in <div>
}
