php+mysql結(jié)合Ajax實(shí)現(xiàn)點(diǎn)贊功能完整實(shí)例

2024-05-04 23:30:47

字體：大中小

供稿：網(wǎng)友

這篇文章主要介紹了php+mysql結(jié)合Ajax實(shí)現(xiàn)點(diǎn)贊功能,以一個(gè)完整實(shí)例形式詳細(xì)分析了實(shí)現(xiàn)點(diǎn)贊功能中涉及的html頁面、Ajax功能及php方法的使用技巧,非常具有實(shí)用價(jià)值,需要的朋友可以參考下

本文實(shí)例講述了php+mysql結(jié)合Ajax實(shí)現(xiàn)點(diǎn)贊功能的方法。分享給大家供大家參考。具體如下：

要實(shí)現(xiàn)點(diǎn)贊功能，有多種實(shí)現(xiàn)方式，這里總結(jié)一下利用Ajax，php和mysql來實(shí)現(xiàn)點(diǎn)贊的數(shù)據(jù)的功能。具體步驟如下：

一、頁面中的HTML代碼部分：

<span>0</span>

<button onclick="goodplus(1);">good+1</button>

<span>0</span>

<button onclick="goodplus(2);">good+1</button>

<span>0</span>

<button onclick="goodplus(3);">good+1</button>

<span>0</span>

<button onclick="goodplus(4);">good+1</button>

二、寫javascript

1、實(shí)現(xiàn)上面的button的點(diǎn)擊事件goodplus

var span = document.getElementsByTagName('span');//獲取存放點(diǎn)贊數(shù)的dom

var num; //點(diǎn)贊數(shù)

var flag = 0; //不同情況的標(biāo)記

function goodplus(gindex){

flag = 1;

num = parseInt(span.item(gindex-1).innerHTML);

if(checkcookie(gindex) == true){

num = num + 1;

senddata(gindex); //通過Ajax修改頁面上的數(shù)據(jù)

}else{

alert("你已經(jīng)點(diǎn)過贊咯！")

}

}

2、頁面一打開時(shí)就應(yīng)該更新點(diǎn)贊數(shù)據(jù)

for(var i = 1; i < span.length + 1; i++){

senddata(i);

}

3、通過Ajax獲取數(shù)據(jù)senddata函數(shù)

function senddata(aindex){

var xmlhttp;

var txt;

if(window.XMLHttpRequest){

xmlhttp=new XMLHttpRequest();

}else{

xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");

}

xmlhttp.onreadystatechange=function(){

if(xmlhttp.readyState == 4 && xmlhttp.status == 200){

txt = xmlhttp.responseText; //獲取返回的數(shù)據(jù)

var cookieindex = aindex - 1;

document.getElementsByTagName('span').item(cookieindex).innerHTML = txt; //賦值

}

}

xmlhttp.open("GET","路徑/index.php?num=" + num + '&flag=' + flag + '&aindex=' + aindex,true);

xmlhttp.send();

}

4、通過設(shè)置cookie來判斷是否已經(jīng)點(diǎn)贊，如果有cookie則提示已經(jīng)點(diǎn)贊，如果沒有cookie則允許點(diǎn)贊，而且會(huì)設(shè)置cookie

//判斷是否已經(jīng)存在了cookie

function checkcookie(gindex){

var thiscookie = 'goodplus' + gindex;

var mapcookie = getCookie(thiscookie)

if (mapcookie!=null && mapcookie!=""){

return false;

}else {

setCookie(thiscookie,thiscookie,365);

return true;

}

}

//獲取cookie

function getCookie(c_name){//獲取cookie，參數(shù)是名稱。

if (document.cookie.length > 0){//當(dāng)cookie不為空的時(shí)候就開始查找名稱

c_start = document.cookie.indexOf(c_name + "=");

if (c_start != -1){ //如果開始的位置不為-1就是找到了、找到了之后就要確定結(jié)束的位置

c_start = c_start + c_name.length + 1 ;

//cookie的值存在名稱和等號(hào)的后面，所以內(nèi)容的開始位置應(yīng)該是加上長(zhǎng)度和1

c_end = document.cookie.indexOf(";" , c_start);

if (c_end == -1) {

c_end = document.cookie.length;

}

return unescape(document.cookie.substring(c_start , c_end));//返回內(nèi)容，解碼。

}

}

return "";

}

//設(shè)置cookie

function setCookie(c_name,value,expiredays){

//存入名稱，值，有效期。有效期到期事件是今天+有效天數(shù)。然后存儲(chǔ)cookie，

var exdate=new Date();

exdate.setDate( exdate.getDate() + expiredays )

document.cookie = c_name + "=" + escape(value) + ((expiredays==null) ? "" : "; expires=" + exdate.toGMTString())

}

三、index.php頁面：

<?php

$num = $_GET['num'];

$aindex = $_GET['aindex'];

$con = mysql_connect("localhost","root","");

if (!$con){

die('Could not connect: ' . mysql_error());

}

mysql_select_db("goodplus", $con);

$sql0s = "SELECT * FROM `good` where `id` = ".$aindex;

$sql0 = mysql_query($sql0s);

if($_GET['flag'] == 0){

while($row = mysql_fetch_array($sql0)){

echo $row['value'];

}

}else if($_GET['flag'] == 1){

$sql="UPDATE `goodplus`.`good` SET `value` = '".$num."' WHERE `good`.`id` = ".$aindex;

if (!mysql_query($sql,$con)){

die('Error: ' . mysql_error());

}

echo $num;

}

mysql_close($con)

?>

四、最終的index.html頁面如下：

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml">

<head>

<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />

<title>無標(biāo)題文檔</title>

</head>

<body>

<span>0</span>

<button onclick="goodplus(1);">good+1</button>

<span>0</span>

<button onclick="goodplus(2);">good+1</button>

<span>0</span>

<button onclick="goodplus(3);">good+1</button>

<span>0</span>

<button onclick="goodplus(4);">good+1</button>

<script type="text/javascript">

var span = document.getElementsByTagName('span');

var num;

var flag = 0;

for(var i = 1; i < span.length + 1; i++){

senddata(i);

}

function goodplus(gindex){

flag = 1;

num = parseInt(span.item(gindex-1).innerHTML);

if(checkcookie(gindex) == true){

numnum = num + 1;

senddata(gindex);

}else{

alert("你已經(jīng)點(diǎn)過贊咯！")

}

}

function senddata(aindex){

var xmlhttp;

var txt;

if(window.XMLHttpRequest){

xmlhttp=new XMLHttpRequest();

}else{

xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");

}

xmlhttp.onreadystatechange=function(){

if(xmlhttp.readyState == 4 && xmlhttp.status == 200){

txt = xmlhttp.responseText;

var cookieindex = aindex - 1;

document.getElementsByTagName('span').item(cookieindex).innerHTML = txt;

}

}

xmlhttp.open("GET","/ajax/json/index.php?num=" + num + '&flag=' + flag + '&aindex=' + aindex,true);

xmlhttp.send();

}

//判斷是否已經(jīng)存在了cookie

function checkcookie(gindex){

var thiscookie = 'sdcity_foodmap_goodplus' + gindex;

var mapcookie = getCookie(thiscookie)

if (mapcookie!=null && mapcookie!=""){

return false;

}else {

setCookie(thiscookie,thiscookie,365);

return true;

}

}

//獲取cookie

function getCookie(c_name){

//獲取cookie，參數(shù)是名稱。

if (document.cookie.length > 0){

//當(dāng)cookie不為空的時(shí)候就開始查找名稱

c_start = document.cookie.indexOf(c_name + "=");

if (c_start != -1){

//如果開始的位置不為-1就是找到了、找到了之后就要確定結(jié)束的位置

c_startc_start = c_start + c_name.length + 1 ;

//cookie的值存在名稱和等號(hào)的后面，所以內(nèi)容的開始位置應(yīng)該是加上長(zhǎng)度和1

c_end = document.cookie.indexOf(";" , c_start);

if (c_end == -1) {

c_end = document.cookie.length;

}

return unescape(document.cookie.substring(c_start , c_end));//返回內(nèi)容，解碼。

}

}

return "";

}

//設(shè)置cookie

function setCookie(c_name,value,expiredays){

//存入名稱，值，有效期。有效期到期事件是今天+有效天數(shù)。然后存儲(chǔ)cookie，

var exdate=new Date();

exdate.setDate( exdate.getDate() + expiredays )

document.cookie = c_name + "=" + escape(value) + ((expiredays==null) ? "" : "; expires=" + exdate.toGMTString())

}

</script>

</body>

</html>