Ajax异步请求PHP数据,ajax异步php
Ajax异步请求PHP数据,ajax异步php
来源:http://www.ido321.com/1138.html
接到了老师的一个作业,实现的布局如图:
如果输入了科室ID,科室名字只显示与ID对应的,若没有输入,则显示全部,然后根据I科室名字的值,在所属大科中的文本框自动显示科室名字所在的大科。例如:选择了心血管内科,则在所属大科显示内科。
主要代码如下:
根据ID请求科室
<span>function</span><span> showHint(str) { <span>var</span> xmlhttp; <span>if</span> (window.XMLHttpRequest) {<span>// IE7+, Firefox, Chrome, Opera, Safari</span> xmlhttp=<span>new</span> XMLHttpRequest(); } <span>else</span> {<span>// IE6, IE5</span> xmlhttp=<span>new</span> ActiveXObject(<span>"Microsoft.XMLHTTP"</span>); } xmlhttp.onreadystatechange=<span>function</span>() { <span>if</span> (xmlhttp.readyState==4 && xmlhttp.status==200) { document.getElementById(<span>"txtHint"</span>).innerHTML=xmlhttp.responseText; } } xmlhttp.open(<span>"GET"</span>,<span>"keshi.php?q="</span>+str,<span>true</span>); xmlhttp.send(); }</span>
keshi.php:
<span><?php <span>/*防止恶意调用*/</span> define(<span>"TEST"</span>,<span>'test'</span>); <span>// 引入文件</span> <span>include_once</span> <span>'mysql.func.php'</span>; <span>// 数据库初始化</span> connectMySQL(); selectDB(); setZiFuJi(); <span>//获得来自 URL 的 q 参数</span> $q=$_GET[<span>"q"</span>]; <span>//如果 q 是数字或者数字字符串</span> <span>if</span> (is_numeric($q)) { $q = intval($q); $hint=<span>""</span>; $resultDKQ = queryDB(<span>"select name from table_dake where id=$q"</span>); $hint = <span>'科室名字:<select name="ksname" id="ksname" onchange="show(this.options[this.selectedIndex].value)">'</span>; <span>while</span> (!!$rowDKQ = fetchAssoc($resultDKQ)) { $hint .= <span>'<optgroup label='</span>.$rowDKQ[<span>'name'</span>].<span>'>'</span>; $resultKSQ = queryDB(<span>"select table_dake.id,table_keshi.sid,table_keshi.name from table_dake,table_keshi where table_dake.name='{$rowDKQ['name']}' and table_keshi.sid=table_dake.id"</span>); <span>while</span>(!!$rowKSQ = fetchAssoc($resultKSQ)) { $hint .= <span>'<option>'name'</span>].<span>'>'</span>.$rowKSQ[<span>'name'</span>].<span>'</option>'</span>; } $hint .= <span>'</optgroup>'</span>; } } <span>// 不是数字</span> <span>else</span> { $resultDK = queryDB(<span>"select table_dake.name from table_dake"</span>); $hint = <span>'科室名字:<select name="ksname" id="ksname" onchange="show(this.options[this.selectedIndex].value)">'</span>; <span>while</span> (!!$rowDK = fetchAssoc($resultDK)) { $hint .= <span>'<optgroup label='</span>.$rowDK[<span>'name'</span>].<span>'>'</span>; $resultKS = queryDB(<span>"select table_dake.id,table_keshi.sid,table_keshi.name from table_dake,table_keshi where table_dake.name='{$rowDK['name']}' and table_keshi.sid=table_dake.id"</span>); <span>while</span>(!!$rowKS = fetchAssoc($resultKS)) { $hint .= <span>'<option>'name'</span>].<span>'>'</span>.$rowKS[<span>'name'</span>].<span>'</option>'</span>; } $hint .= <span>'</optgroup>'</span>; } } $response=$hint; <span>//输出响应</span> <span>echo</span> $response; ?></span>
效果:
未输入ID如上图,输入ID在下图:
下一篇:百家搜索:在网站中添加Google、百度等搜索引擎
在S端直接ECHO '字符串';或 EXIT(json_encode(数组));就行了,
每次请求是没问题的,但是每次请求肯定会有延时。异步的问题只是会有延时,不会存在接收不到返回值的问题,收不到返回值肯定是你哪里写错了。
同时你这个情况我的比较建议一次就把数据都请求过来,存在客户端这边,然后根据需要显示就可以了。
希望对你有帮助!

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