我想改变按钮上的默认文本,即“选择文件”,当我们使用input=" File"。
我该怎么做呢?也可以看到,在图像按钮是在文本的左侧。我怎么把它放在文本的右边?
我想改变按钮上的默认文本,即“选择文件”,当我们使用input=" File"。
我该怎么做呢?也可以看到,在图像按钮是在文本的左侧。我怎么把它放在文本的右边?
当前回答
从这个问题的答案,我修复了许多评论说,不工作,这是它没有显示多少文件用户选择。
<label for="uploadedFiles" class="btn btn-sm btn-outline-primary">Choose files</label>
<input type="file" name="postedFiles" id="uploadedFiles" multiple="multiple" hidden onchange="javascript:updateList()" />
<input class="btn btn-primary mt-2 btn-action" type="submit" value="Send" formmethod="post" formaction="@Url.Action("Create")" /><br />
<span id="selected-count">Selected files: 0</span>
<script>
updateList = function () {
var input = document.getElementById('uploadedFiles');//list of files user uploaded
var output = document.getElementById('selected-count');//element displaying count
output.innerHTML = 'Selected files: ' + input.files.length;
}
</script>
你可以很容易地通过显示文件名来改进它,而不是你想做的任何事情,但我想要的是通知用户他们已经选择了文件。
其他回答
这可能会在将来帮助别人,你可以为输入设置你喜欢的标签,把你想要的任何东西放在里面,隐藏输入,显示为none。
它在iOS的cordova上完美地工作
<link href=“https://cdnjs.cloudflare.com/ajax/libs/ratchet/2.0.2/css/ratchet.css” rel=“stylesheet”/> <label for=“imageUpload” class=“btn btn-primary btn-block btn-outlined”>Seleccionar imagenes</label> <输入类型=“文件” id=“图像上传” 接受=“图像/*” 样式=“显示:无”>
这是不可能的。否则,你可能需要使用Silverlight或Flash上传控件。
每个浏览器都有自己的控件呈现方式,因此您不能更改控件的文本或方向。
如果你想要一个html/css的解决方案,而不是Flash或silverlight的解决方案,你可能想尝试一些“类型”的技巧。
http://www.quirksmode.org/dom/inputfile.html
http://www.shauninman.com/archive/2007/09/10/styling_file_inputs_with_css_and_the_dom
就我个人而言,因为大多数用户坚持使用他们所选择的浏览器,因此可能习惯于在默认呈现中看到控件,如果他们看到不同的内容(取决于您所处理的用户类型),他们可能会感到困惑。
这是一种非常简单的纯css创建自定义输入文件的方法。
使用标签,但是从前面的回答中可以知道,标签不会调用onclick firefox中的函数,可能是一个bug,但与以下内容无关。
<label for="file" class="custom-file-input"><input type="file" name="file" class="custom-file-input"></input></label>
你要做的就是将标签样式设置成你想要的样子
.custom-file-input {
color: transparent;/* This is to take away the browser text for file uploading*/
/* Carry on with the style you want */
background: url(../img/doc-o.png);
background-size: 100%;
position: absolute;
width: 200px;
height: 200px;
cursor: pointer;
top: 10%;
right: 15%;
}
现在简单地隐藏实际的输入按钮,但你不能将其设置为可见:隐藏
所以通过设置不透明度:0来让它不可见;
input.custom-file-input {
opacity: 0;
position: absolute;/*set position to be exactly over your input*/
left: 0;
top: 0;
}
现在,你可能已经注意到,我在标签上有和输入字段相同的类,这是因为我希望两者具有相同的样式,因此,无论你在哪里点击标签,你实际上是在点击不可见的输入字段。
Below is an example of a stylized upload button that will read an image, compress it, and download the resulting image. It works by hiding the actual input element, and then through some trickery we make it so that when you click on our fake file uploader it uses the actual input element to pop up the window for choosing a file. By using this method we get 100% control over how the file uploader looks since we are using our own element instead of styling the file upload menu. It also makes it easy to add drag and drop functionality in the future if we ever want to do that.
然后我写了一系列关于这个文件上传按钮的博文。
'use strict' var AMOUNT = 10 var WIDTH = 600 var HEIGHT = 400 var canvas = document.getElementById('canvas') canvas.width = WIDTH canvas.height = HEIGHT //here's how I created the clickable area //user clicks the clickable area > we send a click event //to the file opener > the file opener clicks on the open //file button > the open file dialogue pops up function clickableAreaListener(e){ let clickEvent = new CustomEvent("click",{"from":"fileOpenerHandler"}); document.getElementById("fileOpener").dispatchEvent(clickEvent); } function fileOpenerListener(e) { document.getElementById("file-btn").click(); e.preventDefault(); } function fileSelectedListener(e){ readFiles(e.target.files); } document.getElementById('file-btn').addEventListener('change', fileSelectedListener); document.getElementById("clickable-area").addEventListener('click', clickableAreaListener); document.getElementById("fileOpener").addEventListener("click", fileOpenerListener); function readFiles(files){ files = [].slice.call(files); //turning files into a normal array for (var file of files){ var reader = new FileReader(); reader.onload = createOnLoadHandler(file); reader.onerror = fileErrorHandler; //there are also reader.onloadstart, reader.onprogress, and reader.onloadend handlers reader.readAsDataURL(file); } } function fileErrorHandler(e) { switch(e.target.error.code) { case e.target.error.NOT_FOUND_ERR: throw 'Image not found'; break; case e.target.error.NOT_READABLE_ERR: throw 'Image is not readable'; break; case e.target.error.ABORT_ERR: break; default: throw 'An error occurred while reading the Image'; }; } function createOnLoadHandler(file){ console.log('reading ' + file.name + ' of type ' + file.type) //file.type will be either image/jpeg or image/png function onLoad(e){ var data = e.target.result display(data); var compressedData = compressCanvas(AMOUNT) download(compressedData) } return onLoad } function display(data){ var img = document.createElement('img'); img.src = data; var context = canvas.getContext('2d') context.clearRect(0, 0, WIDTH, HEIGHT); context.drawImage(img, 0, 0, WIDTH, HEIGHT); } function compressCanvas(){ return canvas.toDataURL('image/jpeg', AMOUNT / 100); } function download(data) { function b64toBlob(b64Data, contentType, sliceSize) { contentType = contentType || ''; sliceSize = sliceSize || 512; var byteCharacters = atob(b64Data); var byteArrays = []; for (var offset = 0; offset < byteCharacters.length; offset += sliceSize) { var slice = byteCharacters.slice(offset, offset + sliceSize); var byteNumbers = new Array(slice.length); for (var i = 0; i < slice.length; i++) { byteNumbers[i] = slice.charCodeAt(i); } var byteArray = new Uint8Array(byteNumbers); byteArrays.push(byteArray); } var blob = new Blob(byteArrays, {type: contentType}); return blob; } var chromeApp = Boolean(chrome && chrome.permissions) if (chromeApp){ chrome.fileSystem.chooseEntry({type:'openDirectory'}, function(entry) { chrome.fileSystem.getWritableEntry(entry, function(entry) { entry.getFile('example.jpg', {create:true}, function(entry) { entry.createWriter(function(writer){ writer.write(b64toBlob(data.slice(23), 'image/jpg')) }) }) }) }) } else { let a = document.createElement("a"); a.href = data; a.download = 'downloadExample.jpg' document.body.appendChild(a) a.click(); window.URL.revokeObjectURL(a.href); a.remove() } } .fileInput { display: none; position: absolute; top: 0; right: 0; font-size: 100px; } #clickable-area{ background: #ccc; width: 500px; display: flex; margin-bottom: 50px; } #clickable-area-text{ margin: auto; } .yellow-button { cursor: pointer; color: white; background: #f1c40f; height: 30px; width: 120px; padding: 30px; font-size: 22px; text-shadow: 0 1px 2px rgba(0, 0, 0, 0.25); } <div id="clickable-area"> <a id='fileOpener'> </a> <input type="file" class="fileInput" id="file-btn" accept="image/*" multiple/> <div class="yellow-button"><span>Shrink Image</span> </div><p id="clickable-area-text">( you can click anywhere in here ) </p> </div> <canvas id="canvas"></canvas>
Stack Overflow的限制似乎阻止了代码片段实际压缩和下载文件。这里完全相同的代码显示了完整的上传/压缩/下载过程实际上按预期工作。