给 cpp2017(慕白兄)另开一 100 分贴：总是已经解决一大半了！补分！关于 javascript 校验的问题！


原贴：

http://community.csdn.net/Expert/topic/5328/5328600.xml?temp=.3653681

老大的这个回复非常有技术性，已经实现了无刷新添加项目到 listbox :

<DIV id= "div1 ">
<INPUT ID= "File1 " TYPE= "file " NAME= "File1 " RUNAT= "server "> <INPUT TYPE= "button " VALUE= "Button " onclick= "javascript:AddFile(); ">
<ASP:LISTBOX id= "ListBox1 " runat= "server "> </ASP:LISTBOX>
<ASP:BUTTON id= "Button1 " runat= "server " Text= "Button "> </ASP:BUTTON> </FONT>
</DIV>


<SCRIPT language= "javascript ">
<!--
function AddFile()
{
var file = document.getElementById( "div1 ").firstChild;
if(file.value == " ")
{
alert( "请选择文件! ");
return;
}
var o = new Option();
var ary = file.value.split( "\\ ");
var filename = ary[ary.length-1];
o.innerText = filename;
o.value = filename;
document.getElementById( "ListBox1 ").appendChild(o);

file.style.display = "none ";
var f = document.createElement( "input ");
f.type = "file ";
f.name = "file "
div1.insertBefore(f,div1.firstChild);



}
//-->
</SCRIPT>

现在有一个问题，就是我想实现一个 点中 listbox 中的一个项后，再点击一个按钮能实现删除这个 listbox 选中项的功能，就是再写一个与 function AddFile()
对应的 function RemoveFile() 的 javascript 函数。


这个问题如果解决了，就完美了！！




[解决办法]
<SCRIPT language= "javascript "> <!-- function AddFile() { var file = document.getElementById( "div1 ").firstChild;if(file.value == " "){alert( "请选择文件! ");return;}var o = new Option();var ary = file.value.split( "\\ ");var filename = ary[ary.length-1];if(CheckOptionsExists(filename,document.getElementById( "ListBox1 "))){alert( "文件已经存在列表中! ");return;}var f = document.createElement( "input ");f.type = "file ";f.name = "file "div1.insertBefore(f,div1.firstChild);o.innerText = filename;o.value = f.uniqueID; document.getElementById( "ListBox1 ").appendChild(o);file.style.display = "none "; } function RemoveFile() {var lst = document.getElementById( "ListBox1 ");if(lst.selectedIndex == -1){alert( "请选择要删除的附件! ");return;}var id = lst.value;div1.removeChild(document.all[id]);lst.removeChild(lst.options[lst.selectedIndex]); } //检查选项是否存在. function CheckOptionsExists(value,ddl) {for(var i=0;i <ddl.options.length;i++){if(ddl.options[i].innerText == value){return true;}}return false; }//--> </SCRIPT>
[解决办法]
<DIV id= "div1 "> <INPUT ID= "File1 " TYPE= "file " NAME= "File1 " runat= "server "> <INPUT TYPE= "button " VALUE= "添加附件 " onclick= "javascript:AddFile(); "> <INPUT TYPE= "button " VALUE= "删除附件 " onclick= "javascript:RemoveFile(); "> <ASP:LISTBOX id= "ListBox1 " Width= "200px " Height= "100px " runat= "server "> </ASP:LISTBOX> <ASP:BUTTON id= "Button1 " runat= "server " Text= "保存 " Width= "60px "> </ASP:BUTTON> </DIV>

[解决办法]
for(int i=0;i <Request.Files.Count;i++){if(Request.Files[i].ContentLength > 0){string filename = System.IO.Path.GetFileName(Request.Files[i].FileName);Request.Files[i].SaveAs(Server.MapPath(filename));this.ListBox1.Items.Add(new ListItem(filename,filename));}this.lResult.Text = "保存成功! ";}
[解决办法]
function RemoveFile() {var lst = document.getElementById( "ListBox1 ");if(lst.selectedIndex == -1){alert( "请选择要删除的附件! ");return;}var id = lst.value;div1.removeChild(document.all[id]);lst.removeChild(lst.options[lst.selectedIndex]);div1.firstChild.style.display = " "; }