AJAX JSON调用失败[重复]

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            <div class="grid--cell mb0 mt8">Closed <span title="2017-03-21 18:59:10Z" class="relativetime">3 years ago</span>.</div>
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I am doing a AJAX call pulling JSON data from a specific site but for some reason I am receiving and error before the call.

Error message:

Uncaught TypeError: Cannot read property 'addEventListener' of null at script.js:2

Code:

var ajaxtest = document.getElementById("dmeo");

ajaxtest.addEventListener("click",function() {
var ourRequest = new XMLHttpRequest();
ourRequest.open("GET","https://learnwebcode.github.io/json-example/animals-1.json")//post if you want to send data
ourRequest.onload = function(){
   // console.log(ourRequest.responseText);//test logging to console.
var ourData = JSON.parse(ourRequest.responseText);
console.log(ourData[0]);
};
ourRequest.send();
});

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typo? var ajaxtest = document.getElementById("dmeo"); should be "demo"?

SOLVED! OK what I ended up doing was just putting it into a onclick event and it works.

function Makecall(){
var ourRequest = new XMLHttpRequest();
ourRequest.open("GET","https://learnwebcode.github.io/json-example/animals-1.json")//post if you want to send data
ourRequest.onload = function(){
   // console.log(ourRequest.responseText);//test logging to console.
var ourData = JSON.parse(ourRequest.responseText);
console.log(ourData[0]);
};
ourRequest.send();
};