2022-07-12第二小组 学习笔记
1.学习收获
<head> <meta charset="UTF-8"> <meta http-equiv="X-UA-Compatible" content="IE=edge"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <title>Document</title> </head> <body> <!-- <p> 账号：<input type="text" id="username"> </p> <p> 密码：<input type="password" id="password"> </p> <p> <input type="button" value="登录" onclick="login()"> </p> <script> function login(){ let username=document.querySelector("#username").value let password=document.querySelector("#password").value if(username=="admin"&& password=="123456"){ alert("登录成功："); }else{ alert("用户名或密码错误："); } } </script> --> <select id="sheng" onchange="city()"> <option>--请先选择省--</option> <option value="jl">吉林省</option> <option value="ln">辽宁省</option> <option value="hlj">黑龙江省</option> </select> <select id="shi" onchange="area()"> <option>--请先选择市--</option></select>
<select id="qu">
<option value="jl">--请先选择区--</option>
</select>
<script>
let sheng = document.querySelector('#sheng')
let shi = document.querySelector('#shi')
let qu = document.querySelector('#qu')
function jilin() {//<option> ++++++ </option>
if (sheng.value == 'jl')
shi.innerHTML = '<option>请先选择市</option><option value="jl">吉林市</option><option value="cc">长春市</option>'
else if (sheng.value == 'ln')
shi.innerHTML = '<option>请先选择市</option><option value="sy">沈阳市</option><option value="dl">大连市</option>'
else if (sheng.value == 'hlj')
shi.innerHTML = '<option>请先选择市</option><option value="dq">大庆市</option><option value="heb">哈尔滨</option>'
else
shi.innerHTML = '<option>请先选择市</option>'
}
function area() {
if (shi.value == 'jl')
qu.innerHTML = '<option>请先选择区</option><option value="cy">昌邑区</option><option value="lt">龙潭区</option>'
else if (shi.value == 'cc')
qu.innerHTML = '<option>请先选择区</option><option value="cy">朝阳区</option><option value="kc">宽城区</option>'
else if (shi.value == 'sy')
qu.innerHTML = '<option>请先选择区</option><option value="hp">和平区</option><option value="dd">大东区</option>'
else if (shi.value == 'dl')
qu.innerHTML = '<option>请先选择区</option><option value="zs">中山区</option><option value="xg">西岗区</option>'
else if (shi.value == 'dq')
qu.innerHTML = '<option>请先选择区</option><option value="lf">龙凤区</option><option value="dt">大同区</option>'
else if (shi.value == 'heb')
qu.innerHTML = '<option>请先选择区</option><option value="ng">南岗区</option><option value="dw">道外区</option>'
else
qu.innerHTML = '<option>请先选择区</option>'
}
function city(){
jilin()
area()
}
</script>
浙公网安备 33010602011771号