blocks|key|2552143|text|在调用onchange时，只需要发送this对象而不是this.value。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|2552144|<input+type='file'+id="upload"+onchange="readURL(this)"+/>|code-block|syntax|javascript|2552145|因为在函数中使用input变量作为this，如|2552146|var+url+=+input.value;//+reading+value+property+of+input+element|2552147|工作演示|2552148|编辑-尝试使用jQuery，如下所示|BOLD|2552149|从输入字段中删除onchange：|2552150|<input+type='file'+id="upload"+>|2552151|将onchange事件绑定到输入字段：|2552152|$(function(){
++$('#upload').change(function(){
++++var+input+=+this;
++++var+url+=+$(this).val();
++++var+ext+=+url.substring(url.lastIndexOf('.')+%2B+1).toLowerCase();
++++if+(input.files+&&+input.files[0]&&+(ext+==+"gif"+%7C%7C+ext+==+"png"+%7C%7C+ext+==+"jpeg"+%7C%7C+ext+==+"jpg"))+
+++++{
++++++++var+reader+=+new+FileReader();

++++++++reader.onload+=+function+(e)+{
+++++++++++$('#img').attr('src',+e.target.result);
++++++++}
+++++++reader.readAsDataURL(input.files[0]);
++++}
++++else
++++{
++++++$('#img').attr('src',+'/assets/no_preview.png');
++++}
++});

});|2552153|jQuery演示|2552154|entityMap|0|LINK|mutability|MUTABLE|url|http://jsfiddle.net/stN8U/2/|1|http://jsfiddle.net/stN8U/3/^0|I|4|R|A|0|0|8|5|H|4|0|0|0|4|0|0|0|2|0|0|0|1|8|0|0|0|8|1|0^^$0|@$1|2|3|4|5|6|7|1D|8|@$9|1E|A|1F|B|C]|$9|1G|A|1H|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|1I|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|1J|8|@$9|1K|A|1L|B|C]|$9|1M|A|1N|B|C]]|D|@]|E|$]]|$1|M|3|N|5|H|7|1O|8|@]|D|@]|E|$I|J]]|$1|O|3|P|5|6|7|1P|8|@]|D|@$9|1Q|A|1R|1|1S]]|E|$]]|$1|Q|3|R|5|6|7|1T|8|@$9|1U|A|1V|B|S]]|D|@]|E|$]]|$1|T|3|U|5|6|7|1W|8|@]|D|@]|E|$]]|$1|V|3|W|5|H|7|1X|8|@]|D|@]|E|$I|J]]|$1|X|3|Y|5|6|7|1Y|8|@$9|1Z|A|20|B|C]]|D|@]|E|$]]|$1|Z|3|10|5|H|7|21|8|@]|D|@]|E|$I|J]]|$1|11|3|12|5|6|7|22|8|@]|D|@$9|23|A|24|1|25]]|E|$]]|$1|13|3|-4|5|6|7|26|8|@]|D|@]|E|$]]]|14|$15|$5|16|17|18|E|$19|1A]]|1B|$5|16|17|18|E|$19|1C]]]]

<p>You need to send <code>this</code> object only instead of <code>this.value</code> while calling onchange</p>

<pre><code>&lt;input type='file' id="upload" onchange="readURL(this)" /&gt;
</code></pre>

<p>because you are using <code>input</code> variable as <code>this</code> in your function, like at line </p>

<pre><code>var url = input.value;// reading value property of input element
</code></pre>

<p><strong><a href="http://jsfiddle.net/stN8U/2/" rel="noreferrer">Working DEMO</a></strong></p>

<p><strong>EDIT</strong> - Try using jQuery like below --</p>

<p>remove onchange from input field :</p>

<pre><code>&lt;input type='file' id="upload" &gt;
</code></pre>

<p>Bind <code>onchange</code> event to input field :</p>

<pre><code>$(function(){
  $('#upload').change(function(){
    var input = this;
    var url = $(this).val();
    var ext = url.substring(url.lastIndexOf('.') + 1).toLowerCase();
    if (input.files &amp;&amp; input.files[0]&amp;&amp; (ext == "gif" || ext == "png" || ext == "jpeg" || ext == "jpg")) 
     {
        var reader = new FileReader();

        reader.onload = function (e) {
           $('#img').attr('src', e.target.result);
        }
       reader.readAsDataURL(input.files[0]);
    }
    else
    {
      $('#img').attr('src', '/assets/no_preview.png');
    }
  });

});
</code></pre>

<p><strong><a href="http://jsfiddle.net/stN8U/3/" rel="noreferrer">jQuery Demo</a></strong></p>


blocks|key|2552156|text|尝试使用以下代码，您将在上传时获得图像预览。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2552157|<input+type='file'+id="upload"+onChange="readURL(this);"/>
<img+id="img"+src="#"+alt="your+image"+/>

+function+readURL(input){
+var+ext+=+input.files[0]['name'].substring(input.files[0]['name'].lastIndexOf('.')+%2B+1).toLowerCase();
if+(input.files+&&+input.files[0]+&&+(ext+==+"gif"+%7C%7C+ext+==+"png"+%7C%7C+ext+==+"jpeg"+%7C%7C+ext+==+"jpg"))+
++++var+reader+=+new+FileReader();
++++reader.onload+=+function+(e)+{
++++++++$('#img').attr('src',+e.target.result);
++++}

++++reader.readAsDataURL(input.files[0]);
}else{
+++++$('#img').attr('src',+'/assets/no_preview.png');
}
}|code-block|syntax|javascript|2552158|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

<p>Try with this code, you will get the image preview while uploading</p>

<pre><code>&lt;input type='file' id="upload" onChange="readURL(this);"/&gt;
&lt;img id="img" src="#" alt="your image" /&gt;

 function readURL(input){
 var ext = input.files[0]['name'].substring(input.files[0]['name'].lastIndexOf('.') + 1).toLowerCase();
if (input.files &amp;&amp; input.files[0] &amp;&amp; (ext == "gif" || ext == "png" || ext == "jpeg" || ext == "jpg")) 
    var reader = new FileReader();
    reader.onload = function (e) {
        $('#img').attr('src', e.target.result);
    }

    reader.readAsDataURL(input.files[0]);
}else{
     $('#img').attr('src', '/assets/no_preview.png');
}
}
</code></pre>


blocks|key|2552183|text|在HTML：<input+type="file"+id="yourFile">中，不要忘记引用js文件或在脚本中的<script></script>之间放置以下脚本：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|2552184|var+fileToRead+=+document.getElementById("yourFile");

fileToRead.addEventListener("change",+function(event)+{
++++var+files+=+fileToRead.files;
++++if+(files.length)+{
++++++++console.log("Filename:+"+%2B+files[0].name);
++++++++console.log("Type:+"+%2B+files[0].type);
++++++++console.log("Size:+"+%2B+files[0].size+%2B+"+bytes");
++++}

},+false);|code-block|syntax|javascript|2552185|entityMap^0|6|X|1L|H|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]|$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|R|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|S|8|@]|D|@]|E|$]]]|L|$]]

<p>in your HTML : <code>&lt;input type="file" id="yourFile"&gt;</code>
don't forget to reference your js file or put the following script between <code>&lt;script&gt;&lt;/script&gt;</code>
in your script :</p>

<pre><code>var fileToRead = document.getElementById("yourFile");

fileToRead.addEventListener("change", function(event) {
    var files = fileToRead.files;
    if (files.length) {
        console.log("Filename: " + files[0].name);
        console.log("Type: " + files[0].type);
        console.log("Size: " + files[0].size + " bytes");
    }

}, false);
</code></pre>


blocks|key|943887|text|简单解没有Jquery|type|unstyled|depth|inlineStyleRanges|offset|length|style|BOLD|entityRanges|data|943888|​|943889|<img+id="output"+src=""+width="100"+height="100">

<input+name="photo"+type="file"+accept="image/*"+onchange="document.getElementById('output').src+=+window.URL.createObjectURL(this.files[0])">|code-block|syntax|javascript|943890|943891|entityMap^0|0|B|0|0|0|0^^$0|@$1|2|3|4|5|6|7|P|8|@$9|Q|A|R|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|S|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|T|8|@]|D|@]|E|$K|L]]|$1|M|3|G|5|6|7|U|8|@]|D|@]|E|$]]|$1|N|3|-4|5|6|7|V|8|@]|D|@]|E|$]]]|O|$]]

<p><strong>Simple Solution. No Jquery</strong></p>

<p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
<div class="snippet-code">
<pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;img id="output" src="" width="100" height="100"&gt;

&lt;input name="photo" type="file" accept="image/*" onchange="document.getElementById('output').src = window.URL.createObjectURL(this.files[0])"&gt;</code></pre>
</div>
</div>
</p>


blocks|key|943920|text|Below+solution+tested+and+its+working,+hope+it+will+support+in+your+project.
HTML+code:
++++<input+type="file"+name="asgnmnt_file"+id="asgnmnt_file"+class="span8"+
++++style="display:none;"+onchange="fileSelected(this)">
++++<br><br>
++++<img+id="asgnmnt_file_img"+src="uploads/assignments/abc.jpg"+width="150"+height="150"+
++++onclick="passFileUrl()"+style="cursor:pointer;">

JavaScript+code:
++++function+passFileUrl(){
++++document.getElementById('asgnmnt_file').click();
++++}

++++function+fileSelected(inputData){
++++document.getElementById('asgnmnt_file_img').src+=+window.URL.createObjectURL(inputData.files[0])
++++}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|943921|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>Below solution tested and its working, hope it will support in your project.
HTML code:
    &lt;input type="file" name="asgnmnt_file" id="asgnmnt_file" class="span8" 
    style="display:none;" onchange="fileSelected(this)"&gt;
    &lt;br&gt;&lt;br&gt;
    &lt;img id="asgnmnt_file_img" src="uploads/assignments/abc.jpg" width="150" height="150" 
    onclick="passFileUrl()" style="cursor:pointer;"&gt;

JavaScript code:
    function passFileUrl(){
    document.getElementById('asgnmnt_file').click();
    }

    function fileSelected(inputData){
    document.getElementById('asgnmnt_file_img').src = window.URL.createObjectURL(inputData.files[0])
    }
</code></pre>


<p>onchange event is not working. What am I supposed to do to get result on same page. I dont want to redirect to any other page to upload image. Is this issue is because of opencart? I dont know if it is correct to write like this in cpanel. I am using opencart and cpanel. Is there any other way?</p>

<p><strong>HTML</strong></p>

<pre><code> &lt;input type='file' id="upload" onchange="readURL(this.value)" /&gt;
    &lt;img id="img" src="#" alt="your image" /&gt;
</code></pre>

<p><strong>script</strong></p>

<pre><code>function readURL(input) {
var url = input.value;
var ext = url.substring(url.lastIndexOf('.') + 1).toLowerCase();
if (input.files &amp;&amp; input.files[0]&amp;&amp; (ext == "gif" || ext == "png" || ext == "jpeg" || ext == "jpg")) {
    var reader = new FileReader();

    reader.onload = function (e) {
        $('#img').attr('src', e.target.result);
    }
    reader.readAsDataURL(input.files[0]);
}
else{
     $('#img').attr('src', '/assets/no_preview.png');
  }
}
</code></pre>

<p><a href="http://jsfiddle.net/Junkie/stN8U/" rel="noreferrer">JSFiddle</a></p>


onchange file input change img src and change image color

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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onchange事件不起作用。我该怎么做才能在同一页上得到结果。我不想重定向到任何其他网页上传图像。这个问题是因为opencart吗？我不知道在cpanel中这样写是否正确。我正在使用opencart和cpanel。还有别的办法吗？ <input type='file' id="upload" onchange="re...

问改变文件输入，改变img src和改变图像颜色。
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问改变文件输入，改变img src和改变图像颜色。EN