开发asp.net自定义控件介绍

/// <summary>

/// 方法GenerateGetPosScript用于生成一段Javascript代码，其作用是为菜单定位

/// </summary>

/// <returns></returns>

private string GenerateGetPosScript()

{

string getPosScript;

getPosScript = "<script language=/"JavaScript/">/n";

getPosScript = getPosScript + "function getPos(el,sProp) {/n";

getPosScript = getPosScript + "/tvar iPos = 0/n";

getPosScript = getPosScript + "/tel = el.offsetParent;/n";

getPosScript = getPosScript + "/twhile (el!=null) {/n";

getPosScript = getPosScript + "/t/tiPos+=el[/"offset/" + sProp]/n";

getPosScript = getPosScript + "/t/tel = el.offsetParent/n}/n/treturn iPos;}/n";

getPosScript = getPosScript + "</script>/n";

return(getPosScript);

}

/// <summary>

/// 方法TraverseMenuTree用于解析XML文件并生成HTML代码

/// </summary>

/// <param name="node">欲开始解析的节点</param>

/// <returns></returns>

private string TraverseMenuTree(System.Xml.XmlNode node)

{

string s = "";

string rightCode;

string[] Rule = RuleString.Split(',');

if(node!=null&&node.HasChildNodes)

{

s = s + "<table border=/"0/" cellpadding=/"0/" cellspacing="+cellspacing.ToString()+" width=/"100%/" class=/"a/">";

s = s + "<tr align="+mainMenuAlign+" valign=/"middle/" class=/"mainmenu/">";

for(int current=0; current<node.ChildNodes.Count; current++)

{

string MenuLabelString = node.ChildNodes.Item(current).Attributes["Label"].Value;

s = s + "<td height="+mainMenuHeight.ToString()+" ><a href=/"#;/" onMouseOver=/"expandMenu(null,'menu"+current+"',getPos(this,'Left'),getPos(this,'Top')+this.offsetHeight);/" class=/"a/">/n/t/t"+MenuLabelString+"</a></td>/n";

s = s + "<div id=/"menu"+current+"/" class=/"menu/" onMouseOut=/"hideMe();/">";

if(node.ChildNodes.Item(current).FirstChild!=null&&node.ChildNodes.Item(current).FirstChild.HasChildNodes)

{

for(int i=0;i<node.ChildNodes.Item(current).FirstChild.ChildNodes.Count;i++)

{

string ItemLabelString = node.ChildNodes.Item(current).FirstChild.ChildNodes.Item(i).Attributes["Label"].Value;

string ItemURLString="";

if(node.ChildNodes.Item(current).FirstChild.ChildNodes.Item(i).Attributes["URL"] != null)

{

ItemURLString = node.ChildNodes.Item(current).FirstChild.ChildNodes.Item(i).Attributes["URL"].Value;

}

if(node.ChildNodes.Item(current).FirstChild.ChildNodes.Item(i).Attributes["RightCode"] != null)

{

rightCode = node.ChildNodes.Item(current).FirstChild.ChildNodes.Item(i).Attributes["RightCode"].Value;

}

else

{

rightCode = "";

}

foreach(string rule in Rule)

{

if(rule==rightCode || ruleString=="admin")

{

s = s + "/n/t/t<a href=/"#;/" onMouseOver=/"expandMenu('menu"+current+"');/" onclick=/"window.location='"+ItemURLString+"'/">";

s = s + "/n/t/t"+ItemLabelString+"</a><br>";

}

}

}

s = s + "</div>";

}

}

s = s + "</tr>";

}

s = s + "</tr></table>/n/n";

s = s + "<p class=/"a/"></p>/n";

return s;

}

重写方法：

/// <summary>

/// 重写OnInit方法，初始化条件

/// </summary>

/// <param name="e"></param>

protected override void OnInit(System.EventArgs e)

{

base.OnInit(e);

return;

}

/// <summary>

/// 将此控件呈现给指定的输出参数。

/// </summary>

/// <param name="output"> 要写出到的 HTML 编写器 </param>

protected override void Render(HtmlTextWriter output)

{

output.Write(GenerateScript());

output.Write(GenerateHtml());

output.Write(GenerateGetPosScript());

}

XML格式如下：

<?xml version="1.0" encoding="UTF-8"?>

<MenuData ImagesBaseURL="Menuimages/">

<MenuGroup>

<MenuItem Label="文件">

<MenuGroup ExpandOffsetY="1" ExpandOffsetX="-1">

<MenuItem Label="新建" URL="i_New.htm" RightCode="vd_ba"/>

<MenuItem Label="保存" RightCode="vd_ba"/>

</MenuGroup>

</MenuItem>

</MenuGroup>

</MenuData>

如前所述，这个Menu支持权限设置，只要设置它的RuleString属性即可。