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首页 / 网页编程 / ASP.NET / Asp.net自定义控件之单选、多选控件

本文实例为大家分享了Asp.net单选、复选框控件的具体实现代码,供大家参考,具体内容如下

将常用的jquery插件封装成控件也是个不错的选择。

先看看效果:

1.新建类库项目,创建数据源类

 [Serializable] public class Select2Item { public bool Selected { get; set; } public string Text { get; set; } public string Value { get; set; } public Select2Item() { } public Select2Item(string text, string value) {this.Text = text;this.Value = value; } public Select2Item(string text, string value, bool selected) {this.Text = text;this.Value = value;this.Selected = selected; } } 

2.创建控件类CheckList,继承与WebControl,并定义 public List<Select2Item> Items数据项属性。

3.引入脚本文件及样式文件 
a.创建脚本或样式文件,设置文件的属性-生成操作-嵌入的资源

  

b.需要在namespace上添加标记 [assembly: WebResource("命名空间.文件夹名.文件名", "mime类型")]
如:
    [assembly: WebResource("Control.Style.checklist.css", "text/css",PerformSubstitution = true)]
    [assembly: WebResource("Control.Scripts.checklist.js", "application/x-javascript")]
 

 如果css文件里面存在图片的话,同样将图片设置为嵌入的资源,在css中的写法为<%=WebResource("命名空间.文件夹名.文件名")%> 
 PerformSubstitution 表示嵌入式资源的处理过程中是否分析其他Web 资源 URL,并用到该资源的完整路径替换。
c.重写protected override void OnPreRender(EventArgs e),引入嵌入的脚本或样式文件
 if(Page!=null) Page.Header.Controls.Add(LiteralControl),将<script><link>标签放到LiteralControl中,然后将LiteralControl添加到Page.Header中,最后在页面里你就会看到引入的<script><link>标签。

 protected override void OnPreRender(EventArgs e) {if (this.Page != null){StringBuilder sbb = new StringBuilder();sbb.Append(string.Format(STYLE_TEMPLATE, Page.ClientScript.GetWebResourceUrl(this.GetType(), "HandControl.Style.checklist.css")));sbb.Append(string.Format(SCRIPT_TEMPLATE, Page.ClientScript.GetWebResourceUrl(this.GetType(), "HandControl.Scripts.checklist.js")));bool hascss = false;LiteralControl lcc = new LiteralControl(sbb.ToString());lcc.ID = "lccheck";foreach (Control item in Page.Header.Controls){ if (item.ID == "lccheck") hascss = true;}if (!hascss) Page.Header.Controls.Add(lcc);}base.OnPreRender(e); } 

4.重写控件的protected override void Render(HtmlTextWriter writer)方法
这里主要是渲染控件的html,根据你的控件而定。 

 protected override void Render(HtmlTextWriter writer) {if (Items.Count > 0){writer.Write("<div id="div" + this.ClientID + "" class="c01-tag-div" mul="" + (Multiple == true ? "1" : "0") + "">");if (Multiple == false) writer.Write("<input name="tb" + this.ClientID + "" type="hidden" value="" + Items[0].Value + "" />");else writer.Write("<input name="tb" + this.ClientID + "" type="hidden" />");bool first = true;foreach (var item in Items){ if (Multiple == false) { if (item.Selected && first) {writer.Write("<a title="" + item.Text + "" class="c01-tag-item c01-tag-select" val="" + item.Value + "" tag="Y">" + item.Text + "</a>");first = false; } else {writer.Write("<a title="" + item.Text + "" class="c01-tag-item" val="" + item.Value + "" tag="N">" + item.Text + "</a>"); } } else { if (item.Selected)writer.Write("<a title="" + item.Text + "" class="c01-tag-item c01-tag-select" val="" + item.Value + "" tag="Y">" + item.Text + "</a>"); elsewriter.Write("<a title="" + item.Text + "" class="c01-tag-item" val="" + item.Value + "" tag="N">" + item.Text + "</a>"); }}writer.Write("</div>");} } 

5.添加GetSelected方法,返回List<Select2Item>,添加GetSelectValue,返回String(多选以,号隔开)       

 public List<Select2Item> GetSelected() {if (Page != null){var values = Page.Request.Form["tb" + this.ClientID].Split(",");var res = Items.Where(t => values.Contains(t.Value)).ToList();foreach (var item in Items){ if (res.Contains(item)) { item.Selected = true; } else { item.Selected = false; }}return res;}else{return null;} } 
 public string GetSelectValue() {if (Page != null){return Page.Request.Form["tb" + this.ClientID];}return ""; } 

6.保存状态
 你需要重写两个方法protected override object SaveViewState() 、protected override void LoadViewState(object savedState),旨在将Items数据项属性保存到ViewState 

 protected override object SaveViewState() {var valuestr = Page.Request.Form["tb" + this.ClientID];if (!string.IsNullOrEmpty(valuestr)){var values = valuestr.Split(",");var temp = Items.Where(t => values.Contains(t.Value)).ToList();foreach (var item in temp){ item.Selected = true;}}return new object[] { base.SaveViewState(), Items }; } protected override void LoadViewState(object savedState) {object[] vState = (object[])savedState;if (vState[0] != null)base.LoadViewState(vState[0]);if (vState[1] != null)Items = (List<Select2Item>)vState[1]; } 

7.单选和复选的设置,在js中控制
 添加属性 
[Description("获取和设置多选"), DefaultValue(true), Browsable(true), Category("杂项")]
public bool Multiple { get; set; }
 在OnPreRender代码中你会发现Multiple属性会影响div的mul属性值,从而判断是否多选(默认多选)
 8.其它说明
private static readonly string STYLE_TEMPLATE = "<link href="{0}" rel="stylesheet" type="text/css" /> ";
 private static readonly string SCRIPT_TEMPLATE = "<script type="text/javascript" src="{0}"></script> ";

效果图:

以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持脚本之家。