您好，我想使用纯 javascript ajax（无 jquery）来附加表单数据，但我不知道如何从输入文件类型中获取数据
function handleForm(e)
{
e.preventDefault();
var username = document.getElementById('username').value;
var email = document.getElementById('email').value;
var data = new FormData();
data.append('username', username);
data.append('email', email);
data.append('file', ?????); ////// How to get data from input file
var xhr = new XMLHttpRequest();
xhr.open('POST', 'test2.php', true);
xhr.onload = function(e) {
if(this.status == 200) {
console.log(e.currentTarget.responseText);
alert(e.currentTarget.responseText + ' items uploaded.');
}
}
xhr.send(data);
}
...
Username: <input type="text" name="username" id="username"><br/>
Email: <input type="text" name="email" id="email"><br/>
Image: <input type="file" name="file" id="myimg"><br/>
<input type="submit">
</form>
我希望下拉列表具有更多宽度,因为我希望字符串"IT硬件"内联.但我的李宽度并没有扩大.所以字符串"IT硬件转到新行"我需要它每行一行另外,我尝试显示:块; 和边距:自动文本到水平中心,但它不成功.编辑:对不起,我的错误是将水平文本居中,只需使用text-align:center;
$(document).ready(function(){
$("#nav ol li").hover(function(){
$(this).find("ol").show(); //when onmouseover //ol ?? nav ol li ??????????
},
function(){ //when mouseout
$(this).find("ol").hide();
});
});html,body{margin:0px;padding:0px;}
body{background:#cceeff;font-family:"verdana"; }
#wrapper{margin:auto;padding:0px;width:75%;}
#header{margin:0px;padding:0px;width:100%;height:18vh;float:left;
background: #99d6ff;
background-image: url("http://co.lnwfile.com/_/co/_raw/0a/el/r0.jpg"); /* fallback */
background-image: url("http://co.lnwfile.com/_/co/_raw/0a/el/r0.jpg"), linear-gradient(#99d6ff, #006bb3); /* W3C */
background-blend-mode: multiply;
/*background-position: 10% 50%; ??size 100% so this will not work*/
background-size: 100%;
background-repeat: no-repeat;
}
#header h1{margin:0px;padding:0px;/*border-bottom:1px solid #eee;*/font-size:20px;padding-bottom:10px;}
#nav{margin:0px;padding:0px;width:100%;float:left;
background: #80ffe5; /* For browsers that do not support gradients */
background: -webkit-linear-gradient(#80ffe5, #00b38f); /* For Safari …