C#实现带搜索功能的ComboBox（c#搜索框功能怎么实现）

带搜索的combobox就是给combobox一个依赖属性的itemsource，然后通过数据源中是否包含要查询的值，重新给combobox绑定数据源。

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 public class editcombobox : combobox { private bool t = true;//首次获取焦点标志位 private observablecollection<object> bindinglist = new observablecollection<object>();//数据源绑定list private string edittext = "";//编辑文本内容 /// <summary> /// 注册依赖事件 /// </summary> public static readonly dependencyproperty itemssourcepropertynew = dependencyproperty.register("myitemssource", typeof(ienumerable), typeof(editcombobox), new frameworkpropertymetadata(new propertychangedcallback(valuechanged))); /// <summary> /// 数据源改变，添加数据源到绑定数据源 /// </summary> /// <param name="d"></param> /// <param name="e"></param> private static void valuechanged(dependencyobject d, dependencypropertychangedeventargs e) { editcombobox ecb = d as editcombobox; ecb.bindinglist.clear(); //遍历循环操作 foreach (var item in ecb.myitemssource) { ecb.bindinglist.add(item); } } /// <summary> /// 设置或获取combobox的数据源 /// </summary> public ienumerable myitemssource { get { return (ienumerable)getvalue(itemssourcepropertynew); } set { if (value == null) clearvalue(itemssourcepropertynew); else setvalue(itemssourcepropertynew, value); } } /// <summary> /// 重写初始化 /// </summary> /// <param name="e"></param> protected override void oninitialized(eventargs e) { base.oninitialized(e); this.iseditable = true; this.istextsearchenabled = false; this.itemssource = bindinglist; } /// <summary> /// 下拉框获取焦点，首次搜索文本编辑框 /// </summary> /// <param name="e"></param> protected override void ongotfocus(routedeventargs e) { if (t) findtextbox(this); else t = false; } /// <summary> /// 搜索编辑文本框，添加文本改变事件 /// </summary> /// <param name="obj"></param> private void findtextbox(dependencyobject obj) { for (int i = 0; i < visualtreehelper.getchildrencount(obj); i++) { dependencyobject child = visualtreehelper.getchild(obj, i); if (child!=null && child is textbox) { //注册文本改变事件 (child as textbox).textchanged += editcombobox_textchanged; } else { findtextbox(child); } } } /// <summary> /// 文本改变，动态控制下拉条数据源 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void editcombobox_textchanged(object sender, textchangedeventargs e) { textbox tb = sender as textbox; if(tb.isfocused) { this.isdropdownopen = true; if (edittext == this.text) return; edittext = this.text; setlist(edittext); } } /// <summary> /// 组合框关闭，数据源恢复 /// </summary> /// <param name="e"></param> protected override void ondropdownclosed(eventargs e) { base.ondropdownclosed(e); if (myitemssource == null) return; foreach (var item in myitemssource) { if (!bindinglist.contains(item)) bindinglist.add(item); } } /// <summary> /// 过滤符合条件的数据项，添加到数据源项中 /// </summary> /// <param name="txt"></param> private void setlist(string txt) { try { string temp1 = ""; string temp2 = ""; if (myitemssource == null) return; foreach (var item in myitemssource) { temp1 = item.gettype().getproperty(this.displaymemberpath).getvalue(item, null).tostring(); if (string.isnullorempty(this.selectedvaluepath)) { temp2 = ""; } else { temp2 = item.gettype().getproperty(this.selectedvaluepath).getvalue(item, null).tostring(); } if(temp1.contains(txt)||temp2.startswith(txt)) { if (!bindinglist.contains(item)) bindinglist.add(item); } else if (bindinglist.contains(item)) { bindinglist.remove(item); } } } catch (exception ex) { messagebox.show(ex.tostring()); } } }

调用方法就是将数据源绑定到myitemssource上，剩下的就和原有的combobox用法一样了。

复制代码代码如下: <local:editcombobox myitemssource="{binding prolist,mode=twoway}" selecteditem="{binding selpro,mode=twoway}" selectedvaluepath="id" displaymemberpath="name"/>

效果演示

C#实现带搜索功能的ComboBox（c#搜索框功能怎么实现）