标签：精典 multiple list upload element file input new row
<html>
<head>
<!-- Include the javascript -->
<script src="multifile_compressed.js"></script>
</head>
<body>
<!-- This is the form -->
<form enctype="multipart/form-data" action="your_script_here.script" method = "post">
<!-- The file element -- NOTE: it has an ID -->
<input id="my_file_element" type="file" name="file_1" >
<input type="submit">
</form>
Files:
<!-- This is where the output will appear -->
<div id="files_list"></div>
<script>
<!-- Create an instance of the multiSelector class, pass it the output target and the max number of files -->
var multi_selector = new MultiSelector( document.getElementById( 'files_list' ), 3 );
<!-- Pass in the file element -->
multi_selector.addElement( document.getElementById( 'my_file_element' ) );
</script>
</body>
</html>
/**
* Convert a single file-input element into a 'multiple' input list
*
* Usage:
*
* 1. Create a file input element (no name)
* eg. <input type="file" id="first_file_element">
*
* 2. Create a DIV for the output to be written to
* eg. <div id="files_list"></div>
*
* 3. Instantiate a MultiSelector object, passing in the DIV and an (optional) maximum number of files
* eg. var multi_selector = new MultiSelector( document.getElementById( 'files_list' ), 3 );
*
* 4. Add the first element
* eg. multi_selector.addElement( document.getElementById( 'first_file_element' ) );
*
* 5. That's it.
*
* You might (will) want to play around with the addListRow() method to make the output prettier.
*
* You might also want to change the line
* element.name = 'file_' + this.count;
* ...to a naming convention that makes more sense to you.
*
* Licence:
* Use this however/wherever you like, just don't blame me if it breaks anything.
*
* Credit:
* If you're nice, you'll leave this bit:
*
* Class by Stickman -- http://www.the-stickman.com
* with thanks to:
* [for Safari fixes]
* Luis Torrefranca -- http://www.law.pitt.edu
* and
* Shawn Parker & John Pennypacker -- http://www.fuzzycoconut.com
* [for duplicate name bug]
* 'neal'
*/
function MultiSelector( list_target, max ){
// Where to write the list
this.list_target = list_target;
// How many elements?
this.count = 0;
// How many elements?
this.id = 0;
// Is there a maximum?
if( max ){
this.max = max;
} else {
this.max = -1;
};
/**
* Add a new file input element
*/
this.addElement = function( element ){
// Make sure it's a file input element
if( element.tagName == 'INPUT' && element.type == 'file' ){
// Element name -- what number am I?
element.name = 'file_' + this.id++;
// Add reference to this object
element.multi_selector = this;
// What to do when a file is selected
element.onchange = function(){
// New file input
var new_element = document.createElement( 'input' );
new_element.type = 'file';
// Add new element
this.parentNode.insertBefore( new_element, this );
// Apply 'update' to element
this.multi_selector.addElement( new_element );
// Update list
this.multi_selector.addListRow( this );
// Hide this: we can't use display:none because Safari doesn't like it
this.style.position = 'absolute';
this.style.left = '-1000px';
};
// If we've reached maximum number, disable input element
if( this.max != -1 && this.count >= this.max ){
element.disabled = true;
};
// File element counter
this.count++;
// Most recent element
this.current_element = element;
} else {
// This can only be applied to file input elements!
alert( 'Error: not a file input element' );
};
};
/**
* Add a new row to the list of files
*/
this.addListRow = function( element ){
// Row div
var new_row = document.createElement( 'div' );
// Delete button
var new_row_button = document.createElement( 'input' );
new_row_button.type = 'button';
new_row_button.value = 'Delete';
// References
new_row.element = element;
// Delete function
new_row_button.οnclick= function(){
// Remove element from form
this.parentNode.element.parentNode.removeChild( this.parentNode.element );
// Remove this row from the list
this.parentNode.parentNode.removeChild( this.parentNode );
// Decrement counter
this.parentNode.element.multi_selector.count--;
// Re-enable input element (if it's disabled)
this.parentNode.element.multi_selector.current_element.disabled = false;
// Appease Safari
// without it Safari wants to reload the browser window
// which nixes your already queued uploads
return false;
};
// Set row value
new_row.innerHTML = element.value;
// Add button
new_row.appendChild( new_row_button );
// Add it to the list
this.list_target.appendChild( new_row );
};
};
标签：精典,
multiple,
list,
upload,
element,
file,
input,
new,
row
From： https://blog.51cto.com/u_15834343/5887912