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项目管理
HarmonyOS
<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>无标题文档</title>
<script>
function fn1(data) {//比如把fn1函数放入window.load=function(){}的函数里面为什么就不能执行的?是什么原因导致的？就是fn1不是全局函数的话为什么出错了？
var oUl1 = document.getElementById('ul1');
var html = '';
for (var i=0; i<data.length; i++) {
html += '<li>'+data[i]+'</li>';
}
oUl1.innerHTML = html;
}
function fn2(data) {
var oUl2 = document.getElementById('ul2');
var html = '';
for (var i=0; i<data.length; i++) {
html += '<li>'+data[i]+'</li>';
}
oUl2.innerHTML = html;
}
function fn3(data) {
var oUl3 = document.getElementById('ul3');
var html = '';
for (var i=0; i<data.length; i++) {
html += '<li>'+data[i]+'</li>';
}
oUl3.innerHTML = html;
}
</script>
<script>
window.onload = function() {
var oBtn1 = document.getElementById('btn1');
var oBtn2 = document.getElementById('btn2');
oBtn1.onclick = function() {
var oScript = document.createElement('script');
oScript.src = 'getData.php?callback=fn1';
document.body.appendChild(oScript);
}
var oBtn2 = document.getElementById('btn2');
oBtn2.onclick = function() {
var oScript = document.createElement('script');
oScript.src = 'getData.php?t=str&callback=fn2';
document.body.appendChild(oScript);
}
var oBtn3 = document.getElementById('btn3');
oBtn3.onclick = function() {
var oScript = document.createElement('script');
oScript.src = 'getData.php?callback=fn3';
document.body.appendChild(oScript);
}
}
</script>
</head>
<body>
<input type="button" id="btn1" value="加载数字" />
<ul id="ul1"></ul>
<input type="button" id="btn2" value="加载字母" />
<ul id="ul2"></ul>
<input type="button" id="btn3" value="加载字母" />
<ul id="ul3"></ul>
</body>
</html>-----------------PHP文件-----------------
<?php
$t = isset($_GET['t']) ? $_GET['t'] : 'num';
$callback = isset($_GET['callback']) ? $_GET['callback'] : 'fn1';
$arr1 = array('111111','22222222','33333333','4444444','555555555555555555555');
$arr2 = array('aaaaaaaaaaaa','bbbbbbbb','cccccccccccc','ddddddddd','eeeeeeeeeeee');
if ($t == 'num') {
$data = json_encode($arr1);
} else {
$data = json_encode($arr2);
}
echo $callback.'('.$data.');';
简化下问题就是如下代码段:
fn2函数因为在onload函数中定义，此作用域在onload函数内，出了这个函数就不能被访问到
fn1函数定义在全局作用域下，可以被全局访问