添加附件

来源：互联网发布：windows.open 滚动条编辑：程序博客网时间：2024/04/29 10:06

来源：http://hi.baidu.com/adverse/blog/item/e8310a24dd8ebe32c89559c9.html

<html>
<head>
<title>Add Files</title>
<style>
a.addfile {
background-image:url(http://p.mail.163.com/js31style/lib/0703131650/163blue/f1.gif);
background-repeat:no-repeat;
background-position:-823px -17px;
display:block;
float:left;
height:20px;
margin-top:-1px;
position:relative;
text-decoration:none;
top:0pt;
width:80px;
}

input.addfile {
/*left:-18px;*/
}

input.addfile {
cursor:pointer !important;
height:18px;
left:-13px;
filter:alpha(opacity=0);
position:absolute;
top:5px;
width:1px;
z-index: -1;
}
</style>

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';
                 new_element.size = 1;
                 new_element.className = "addfile";

// 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.onclick = 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);
     };
};
</script>
</head>

<body>

<form enctype="multipart/form-data" action="your_script_here.script" method="post">

<a href=# class="addfile">
<input id="my_file_element" class="addfile" type="file" name="file_1" size="1" title="点击选择附件">
</a>
<input type="submit" value=上传>
</form>

Files:

<div id="files_list" style="padding:5px;border:1px;border-style:solid;border-color:#0000ff;height:100px;width:600px;"></div>
<script>

var multi_selector = new MultiSelector(document.getElementById('files_list'), 100);

multi_selector.addElement(document.getElementById('my_file_element'));
</script>

</body>
</html>