ASP.NET对无序列表批量操作的三种方法小结

本篇介绍服务器端asp.net批量操作基于原生html标签的无序列表的三种方法。
方法一，将li元素做成html控件，加上id，用findcontrol方法。

aspx代码：

<form id="form1" runat="server">
<ul>
<li id="li1" runat="server">初始值1</li>
<li id="li2" runat="server">初始值2</li>
<li id="li3" runat="server">初始值3</li>
<li id="li4" runat="server">初始值4</li>
<li id="li5" runat="server">初始值5</li>
<li id="li6" runat="server">初始值6</li>
<li id="li7" runat="server">初始值7</li>
<li id="li8" runat="server">初始值8</li>
</ul>
<asp:button id="button1" runat="server" text="button" onclick="button1_click" />
</form>

aspx.cs代码：

protected void button1_click(object sender, eventargs e)
{
//单击按钮后批量改变li元素的内联文本值及样式
for (int i = 1; i <= 8; i++)
{
htmlgenericcontrol li = this.findcontrol("li" + i) as htmlgenericcontrol;
li.innerhtml = "新值" + i.tostring();
li.attributes.cssstyle.value = "color:red";
}
}

方法二，将ul、li元素做成html控件，用ul控件的controls集合遍历。

aspx代码：

<form id="form1" runat="server">
<ul id="ul1" runat="server">
<li runat="server">初始值1</li>
<li runat="server">初始值2</li>
<li runat="server">初始值3</li>
<li runat="server">初始值4</li>
<li runat="server">初始值5</li>
<li runat="server">初始值6</li>
<li runat="server">初始值7</li>
<li runat="server">初始值8</li>
</ul>
<asp:button id="button1" runat="server" text="button" onclick="button1_click" />
</form>

aspx.cs代码：

private int counter = 1;
protected void button1_click(object sender, eventargs e)
{
//单击按钮后批量改变li元素的内联文本值及样式
foreach (control control in ul1.controls)
{
if (control is htmlgenericcontrol)
{
htmlgenericcontrol li = control as htmlgenericcontrol;
li.innerhtml = "新值" + (counter++).tostring();
li.attributes.cssstyle.value = "color:red";
}
}
}

方法三，利用htmlagilitypack，对元素以dom方式操作。

aspx代码：

<form id="form1" runat="server">
<ul id="ul1" runat="server">
<li>初始值1</li>
<li>初始值2</li>
<li>初始值3</li>
<li>初始值4</li>
<li>初始值5</li>
<li>初始值6</li>
<li>初始值7</li>
<li>初始值8</li>
</ul>
<asp:button id="button1" runat="server" text="button" onclick="button1_click" />
<asp:button id="button2" runat="server" text="测试空回发" />
</form>

aspx.cs代码：

protected void button1_click(object sender, eventargs e)
{
//单击按钮后批量改变li元素的内联文本值及样式
htmldocument htmldoc = new htmldocument();
htmldoc.loadhtml(ul1.innerhtml);
htmlnodecollection lis = htmldoc.documentnode.selectnodes("li");
for (int i = 0; i < lis.count; i++)
{
lis[i].innerhtml = "新值" + (i + 1).tostring();
lis[i].attributes.add("style", "color:red");
}
ul1.innerhtml = htmldoc.documentnode.innerhtml;
}

以上三种方法各有优缺点，可根据实际情况选用。