思路分析：有3种情况
第一种情况，当前页面curPage < 4
第二种情况，当前页面curPage == 4
第三种情况，当前页面curPage>4
此外，还要考虑，当前页码 curPage < pageTotal（总页码）-2，才显示 ...
首先，先是前端的布局样式
<body>
/*首先，在body中添加div id="pagination" */
<div id="pagination">
<!-- 后面会在js中动态追加 ，此处为了，实现前端效果，所以注册
<a id="prevBtn"><</a>
<a id="first">1</a>
<a href="#">2</a>
<a href="#">3</a>
<a href="#">4</a>
<span>...</span>
<a href="#" id="last">10</a>
<a href="#" id="nextBtn">></a>
-->
</div>
</body>
其次，是css代码
*{
margin: 0;
padding: 0;
}
#pagination{
width: 500px;
height: 100px;
border: 2px solid crimson;
margin: 50px auto ;
padding-top: 50px ;
padding-left: 50px;
}
.over,.pageItem{
float: left;
display: block;
width: 35px;
height: 35px;
line-height: 35px;
text-align: center;
}
.pageItem{
border: 1px solid orangered;
text-decoration: none;
color: dimgrey;
margin-right: -1px;/*解决边框加粗问题*/
}
.pageItem:hover{
background-color: #f98e4594;
color:orangered ;
}
.clearfix{
clear: both;
}
.active{
background-color: #f98e4594;
color:orangered ;
}
.banBtn{
border:1px solid #ff980069;
color: #ff980069;
}
#prevBtn{
margin-right: 10px;
}
#nextBtn{
margin-left: 10px;
}
JavaScript代码
<script type="text/JavaScript">
var pageOptions = {pageTotal:10,curPage:7,paginationId:‘‘};
dynamicPagingFunc(pageOptions);
function dynamicPagingFunc(pageOptions){
var pageTotal = pageOptions.pageTotal || 1;
var curPage = pageOptions.curPage||1;
var doc = document;
var paginationId = doc.getElementById(‘‘+pageOptions.paginationId+‘‘) || doc.getElementById(‘pagination‘);
var html = ‘‘;
if(curPage>pageTotal){
curPage =1;
}
/*总页数小于5，全部显示*/
if(pageTotal<=5){
html = appendItem(pageTotal,curPage,html);
paginationId.innerhtml = html;
}
/*总页数大于5时，要分析当前页*/
if(pageTotal>5){
if(curPage<=4){
html = appendItem(pageTotal,curPage,html);
paginationId.innerhtml = html;
}else if(curPage>4){
html = appendItem(pageTotal,curPage,html);
paginationId.innerHTML = html;
}
}
}
function appendItem(pageTotal,curPage,html){
var starPage = 0;
var endPage = 0;
html+=‘<a id="prevBtn"><</a>‘;
if(pageTotal<=5){
starPage = 1;
endPage = pageTotal;
}else if(pageTotal>5 && curPage<=4){
starPage = 1;
endPage = 4;
if(curPage==4){
endPage = 5;
}
}else{
if(pageTotal==curPage){
starPage = curPage-3;
endPage = curPage;
}else{
starPage = curPage-2;
endPage = curPage+1;
}
html += ‘<a id="first">1</a><span>...</span>‘;
}
for(let i = starPage;i <= endPage;i++){
if(i==curPage){
html += ‘<a id="first">‘+i+‘</a>‘;
}else{
html += ‘<a href="#">‘+i+‘</a>‘;
}
}
if(pageTotal<=5){
html+=‘<a href="#" id="nextBtn">></a>‘;
}else{
if(curPage<pageTotal-2){
html += ‘<span>...</span>‘;
}
if(curPage<=pageTotal-2){
html += ‘<a href="#">‘+pageTotal+‘</a>‘;
}
html+=‘<a href="#" id="nextBtn">></a>‘;
}
return html;
}
</script>