function getMax(a, b, c) {
var max = a
if(b > max)
max = b
if(c > max)
max = c
return max
}
function getMin(a, b, c) {
var min = a
if(b < min)
min = b
if(c < min)
min = c
return min
}
console.log(getMax(1, 22, 3))
console.log(getMin(15, 2, 33))
22
2
function getEven(a) {
if (a % 2) {
console.log("i am not even number")
}
else {
console.log("i am even number")
}
}
getEven(22)
getEven(33)
i am even number
i am not even number
<ul class="ct">
<li>这里是</li>
<li>星辉</li>
<li>幸会</li>
</ul>
var arr_li = document.getElementsByTagName('li');
for (var i = 0; i < arr_li.length; i++) {
arr_li[i].addEventListener('click', function(event) {
console.log(event.target.innerText);
}, false);
}
这里是
星辉
幸会
<ul class="ct">
<li>这里是</li>
<li>星辉</li>
<li>幸会</li>
</ul>
<input class="ipt-add-content" placeholder="添加内容">
<button id="btn-add-start">开头添加</button>
<button id="btn-add-end">结尾添加</button>
var arr_li = document.getElementsByTagName('li')
var ele_content = document.getElementsByClassName('ipt-add-content')
var content
var btn_start = document.getElementById('btn-add-start')
var btn_end = document.getElementById('btn-add-end')
for (var i = 0; i < arr_li.length; i++) {
arr_li[i].addEventListener('click', function(event) {
console.log(event.target.innerText);
}, false);
}
btn_start.addEventListener('click', function(event) {
// 用原生js在开头加li元素
content = ele_content[0].value
var node=document.createElement("li");
var textnode=document.createTextNode(content);
node.appendChild(textnode);
document.getElementsByClassName("ct")[0].insertBefore(node, document.getElementsByClassName("ct")[0].firstChild);
ele_content[0].value = ''
}, false)
btn_end.addEventListener('click', function(event) {
// 用原生js在结尾加li元素
content = ele_content[0].value
var node=document.createElement("li");
var textnode=document.createTextNode(content);
node.appendChild(textnode);
document.getElementsByClassName("ct")[0].appendChild(node);
ele_content[0].value = ''
}, false)
<ul class="ct">
<li data-img="1.jpg">鼠标放置查看图片1</li>
<li data-img="2.jpg">鼠标放置查看图片2</li>
<li data-img="3.jpg">鼠标放置查看图片3</li>
</ul>
<div class="img-preview"></div>
// 需要在对应路径放置三张图片
var ele_li = document.getElementsByTagName('li')
var img = document.getElementsByClassName('img-preview')
for (var i = 0; i < ele_li.length; i++) {
ele_li[i].addEventListener('mouseover', function(event) {
var src = event.target.getAttribute('data-img')
img[0].innerHTML = '<img src="' + src + '">'
}, false)
}