DropDownList
(申明:转载)
主要使用递归实现,数据库结构:
![](https://images.cnblogs.com/cnblogs_com/chensubo/db.jpg)
最终样式:
![](https://images.cnblogs.com/cnblogs_com/chensubo/ddl.jpg)
![](https://images.cnblogs.com/cnblogs_com/chensubo/db.jpg)
最终样式:
![](https://images.cnblogs.com/cnblogs_com/chensubo/ddl.jpg)
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protected void Page_Load(object sender, EventArgs e)
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{
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if (!Page.IsPostBack)
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{
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BindDrpClass();
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}
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}
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//绑定顶级分类
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private void BindDrpClass()
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{
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Bll.Class classSystem = new Bll.Class();
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DataTable dt = classSystem.GetClassList("").Tables[0];
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ddlClass.Items.Clear();
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ddlClass.Items.Add(new ListItem("添加根栏目","0"));
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DataRow[] drs = dt.Select("ParentID= " + 0);
16![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
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foreach (DataRow dr in drs)
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{
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string classid = dr["ClassID"].ToString();
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string classname = dr["ClassName"].ToString();
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//顶级分类显示形式
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classname = "╋" + classname;
23![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
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ddlClass.Items.Add(new ListItem(classname, classid));
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int sonparentid = int.Parse(classid);
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string blank = "├";
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//递归子分类方法
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BindNode(sonparentid, dt, blank);
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}
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ddlClass.DataBind();
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}
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//绑定子分类
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private void BindNode(int parentid, DataTable dt, string blank)
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{
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DataRow[] drs = dt.Select("ParentID= " + parentid);
36![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
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foreach (DataRow dr in drs)
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{
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string classid = dr["ClassID"].ToString();
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string classname = dr["ClassName"].ToString();
41![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
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classname = blank + classname;
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ddlClass.Items.Add(new ListItem(classname, classid));
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int sonparentid = int.Parse(classid);
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string blank2 = blank + "─";
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BindNode(sonparentid, dt, blank2);
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}
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}
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