<input type="file" value="Browse" name="avat开发者_如何转开发ar" id="id_avatar" />

I tried to modify the value, but it's not working. How to customize the button text?

Use Bootstrap FileStyle, which is used to style the file fields of forms. It is a plugin for a jQuery-based component library called Twitter Bootstrap

Sample usage:

Include:

<script type="text/javascript" src="js/bootstrap-filestyle.min.js"> </script>

Via JavaScript:

$(":file").filestyle();

Via data attributes:

<input type="file" class="filestyle" data-classButton="btn btn-primary" data-input="false" data-classIcon="icon-plus" data-buttonText="Your label here.">

Hide the file input. Create a new input to capture a click event and forward it to the hidden input:

<input type="button" id="loadFileXml" value="loadXml" onclick="document.getElementById('file').click();" />
<input type="file" style="display:none;" id="file" name="file"/>

You can put an image instead, and do it like this:

HTML:

<img src="/images/uploadButton.png" id="upfile1" style="cursor:pointer" />
<input type="file" id="file1"  name="file1" style="display:none" />

JQuery:

$("#upfile1").click(function () {
    $("#file1").trigger('click');
});

CAVEAT: In IE9 and IE10 if you trigger the onClick in a file input via javascript, the form will be flagged as 'dangerous' and cannot be submitted with javascript, not sure if it can be submitted traditionally.

The "upload file..." text is pre-defined by the browser and can't be changed. The only way to get around this is to use a Flash- or Java-based upload component like swfupload.

Works Perfectly on All Browsers Hope it will work for you too.

HTML:
<input type="file" class="custom-file-input">

CSS:

 .custom-file-input::-webkit-file-upload-button {
  visibility: hidden;
}
.custom-file-input::before {
  content: 'Select some files';
  display: inline-block;
  background: -webkit-linear-gradient(top, #f9f9f9, #e3e3e3);
  border: 1px solid #999;
  border-radius: 3px;
  padding: 5px 8px;
  outline: none;
  white-space: nowrap;
  -webkit-user-select: none;
  cursor: pointer;
  text-shadow: 1px 1px #fff;
  font-weight: 700;
  font-size: 10pt;
}
.custom-file-input:hover::before {
  border-color: black;
}
.custom-file-input:active::before {
  background: -webkit-linear-gradient(top, #e3e3e3, #f9f9f9);
}

Change content: 'Select some files'; with the text you want within ''

IF NOT WORKING WITH firefox then use this instead of input:

<label class="custom-file-input" for="Upload" >
</label>

<input id="Upload" type="file" multiple="multiple" name="_photos" accept="image/*" style="visibility: hidden">

Simply

<label class="btn btn-primary">
  <i class="fa fa-image"></i> Your text here<input type="file" style="display: none;"  name="image">
</label>

[Edit with snippet]

<link href="https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/css/bootstrap.min.css" rel="stylesheet"/>
<link href="https://stackpath.bootstrapcdn.com/font-awesome/4.7.0/css/font-awesome.min.css" rel="stylesheet"/>

<label class="btn btn-primary">
<i class="fa fa-image"></i> Your text here<input type="file" style="display: none;" name="image">
</label>

I think this is what you want:

<button style="display:block;width:120px; height:30px;" onclick="document.getElementById('getFile').click()">Your text here</button>


<input type='file' id="getFile" style="display:none"> 

This is a JQuery plugin to change the button text of an input file element.

Example HTML:

<input type="file" id="choose-file" />

Example JS:

$('#choose-file').inputFileText({
    text: 'Select File'
});

Result:

<input id="uploadFile" placeholder="Choose File" disabled="disabled" />
<div class="fileUpload btn btn-primary">
    <span>Your name</span>
    <input id="uploadBtn" type="file" class="upload" />
</div>

JS

document.getElementById("uploadBtn").onchange = function () {
    document.getElementById("uploadFile").value = this.value;
 };

more http://geniuscarrier.com/how-to-style-a-html-file-upload-button-in-pure-css/

Use <label> for the caption

<form enctype='multipart/form-data' action='/uploads.php' method=post>
<label for=b1>
    <u>Your</u> caption here
<input style='width:0px' type=file name=upfile id=b1
 onchange='optionalExtraProcessing(b1.files[0])'
 accept='image/png'>
</label>
</form>

This works without any javascript. You can decorate the label to any degree of complexity, to your heart's content. When you click on the label, the click automatically gets redirected to the file input. The file input itself can be made invisible by any method. If you want the label to appear like a button, there are many solutions, e.g.:

label u {
    -webkit-appearance: button;
    -moz-appearance: button;
    appearance: button;

    text-decoration: none;
    color: initial;
}

I know, nobody asked for it but if anybody is using bootstrap, it can be changed through Label and CSS Pseudo-selector.

For changing button text:

.custom-file-label::after {
  content: "What's up?";
}

For changing field text:

<label class="custom-file-label" for="upload">Drop it like it's hot</label>

Here's a fiddle.

In Addition to MushyPeas answer, you can add a label to show the filename like so (no jQuery needed):
Credits also to this answer.

<input type="button" id="click-input" value="Write anything" onclick="document.getElementById('file').click();" />
<label for="click-input" id="file-name">Bla bla</label>
<input type="file" style="display:none;" id="file">
<script>
    inputElement = document.getElementById('file')
    labelElement = document.getElementById('file-name')
    inputElement.onchange = function(event) {
        var path = inputElement.value;
        if (path) {
            labelElement.innerHTML = path.split(/(\\|\/)/g).pop()
        } else {
            labelElement.innerHTML = 'Bla bla'
        } 
    }
</script>

Only CSS & bootstrap class

<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bootstrap@4.6.0/dist/css/bootstrap.min.css" integrity="sha384-B0vP5xmATw1+K9KRQjQERJvTumQW0nPEzvF6L/Z6nronJ3oUOFUFpCjEUQouq2+l" crossorigin="anonymous">

<div class="col-md-4 input-group">
  <input class="form-control" type="text" />
  <div class="input-group-btn">
    <label for="files" class="btn btn-default">browse</label>
    <input id="files" type="file" class="btn btn-default" style="visibility:hidden;" />
  </div>
</div>

EDIT: I see now by the comments that you are asking about the button text, and not the file path. My bad. I'll leave my original answer below in case someone else who stumbles upon this question interprets it the way I originally did.

2nd EDIT: I had deleted this answer because I decided that I misunderstood the question and my answer was not relevant. However, comments in another answer indicated that people still wanted to see this answer so I'm undeleting it.

MY ORIGINAL ANSWER (I thought the OP was asking about the path, not the button text):

This is not a supported feature for security reasons. The Opera web browser used to support this but it was removed. Think about what would be possible if this were supported; You could make a page with a file upload input, pre-populate it with a path to some sensitive file and then auto-submit the form using javascript triggered by the onload event. This would happen too fast for the user to do anything about it.

Here is a way to "change" the text of an input with file type, with pure HTML and javascript:

<input id='browse' type='file' style='width:0px'>
<button id='browser' onclick='browse.click()'>
    *The text you want*
</button>

In Bootstrap +4.5 you can simply add this to your code:

.custom-file-input~.custom-file-label::after {
  content: "Your custom text ...";
}

<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bootstrap@4.6.0/dist/css/bootstrap.min.css" integrity="sha384-B0vP5xmATw1+K9KRQjQERJvTumQW0nPEzvF6L/Z6nronJ3oUOFUFpCjEUQouq2+l" crossorigin="anonymous">

<div class="custom-file">
  <input type="file" class="custom-file-input">
  <label class="custom-file-label">Your custom placeholder ...</label>
</div>

What about icons without using real images and "interactivity"?

Check the following example that doesn't use any image, not even javascript, and also it is interactive in the sense that changes its look on mouse events as on mouse-over and on mouse left or right click.

input
{
  padding: 10px;
  width: 100%;
}

input::file-selector-button
{
  display: none;
}

input::before
{
  border: 1px solid red;
  border-radius: 3px 8px 3px 8px;
  color: red;
  content: attr(value)' Some more text';
  margin: 25px;
  padding: 5px;
}

input:hover:before
{
  border: 1px groove blue;
  background: lime;
}

input:active:before
{
  border: 1px groove blue;
  background: yellow;
}

<input type="file" value="