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js 触发select onchange事件代码

点评:select 或text的onchange事件需要手动(通过键盘输入)改变select或text的值才能触发,本文为大家介绍下使用js触发select onchange事件!

例如,在页面加载完成以后,需要触发一个onChange事件,在js中用document.getElementById("province").value="湖北";直接给select或text赋值是不行的,要想实现手动触发onchange事件,需要在js给select赋值后,加入下面的语句

document.getElementById("province").fireEvent('onchange') 来实现,

复制代码 代码如下:

<head>

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

<title>无标题文档</title>

<script type="text/javascript">

var provinces = new Array();

provinces["湖北"] = ["武汉","襄阳","随州","宜昌","十堰"];

provinces["四川"] = ["成都","内江","达州"];

provinces["河南"] =["郑州","南阳","信阳","漯河"];

function changeProvince()

{

var prov = document.getElementById("province").value;

var city =document.getElementById("city");

city.options.length =0;

for(var i in provinces[prov])

{

city.options.add(new Option(provinces[prov][i],provinces[prov][i]));

}

}

window.onload = function(){

var province = document.getElementById("province");

for(var index in provinces)

{

//alert(index);

province.options.add(new Option(index,index));

}

province.fireEvent("onchange");

};

</script>

</head>

<body>

省份:<select id="province" onchange= "changeProvince()"></select>

城市:<select id="city"></select>

</body>

</html>