C # Implementation of combobox_c# tutorial with search function

The

ComboBox with a search is the Itemsource that gives ComboBox a dependent property, and then the ComboBox bound data source through whether the data source contains the value to query.

public class Editcombobox:combobox {private bool t = true;//First gain focus logo bit private observablecollection<object  > bindinglist = new observablecollection<object> ()//Data source binding list private String edittext = "";//Edit Text content/// <summary>///Registration Dependency event///</summary> public static readonly DependencyProperty Itemssourceproperty New = Dependencyproperty.register ("Myitemssource", typeof (IEnumerable), typeof (Editcombobox), new
    Frameworkpropertymetadata (New Propertychangedcallback (valuechanged)); <summary>///Data source change, add data source to binding data source///</summary>///<param name= "D" ></param>// /<param name= "E" ></param> private static void ValueChanged (DependencyObject D, Dependencypropertychangede
      Ventargs e) {Editcombobox ECB = d as editcombobox;
      Ecb.bindingList.Clear (); Traversal loop operation foreach (Var item in ECB.)
      Myitemssource) {ECB.BINDINGLIST.ADD (item); }
    }
    ///<summary>///set or get ComboBox data source///</summary> public IEnumerable Myitemssource {gets
      {return (IEnumerable) GetValue (itemssourcepropertynew);
        set {if (value = = null) clearvalue (itemssourcepropertynew);
      else SetValue (itemssourcepropertynew, value); }///<summary>///rewrite initialization///</summary>///<param name= "E" ></param> PR otected override void OnInitialized (EventArgs e) {base.
      OnInitialized (e); This.
      Iseditable = true; This.
      istextsearchenabled = false; This.
    ItemsSource = BindingList;
    ///<summary>///dropdown box gets focus, first search text edit box///</summary>///<param name= "E" ></param>
      protected override void OnGotFocus (RoutedEventArgs e) {if (t) Findtextbox (this);
    else T = false; ///<summary>///Search Edit text box, add text Change event///</summary>///<param name= "obj" ></param> private void Findtextbox (DependencyObject obj) { for (int i = 0; i < visualtreehelper.getchildrencount (obj); i++) {DependencyObject child = Visualtre
        Ehelper.getchild (obj, i); if (Child!=null && child is textbox) {//Register text Change event (child as TextBox).
        TextChanged + = editcombobox_textchanged;
        else {findtextbox (child); }}///<summary>///text changes, dynamic control dropdown data source///</summary>///<param name= "Sender" &G t;</param>///<param name= "E" ></param> private void Editcombobox_textchanged (object sender, Tex
      Tchangedeventargs e) {textbox TB = sender as TextBox; if (TB. isfocused) {this.
        Isdropdownopen = true; if (EditText = = this.
        Text) return; EditText = this.
        Text;
      Setlist (EditText); }
    }
    /<summary>///combo box closed, data source restore///</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>///filter Eligible data items, add to the data source item///</summary>///<param name= "TXT" &GT;&L
        t;/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 ());
 }
    }
  }

The calling method is to bind the data source to the Myitemssource, and the rest is the same as the original ComboBox usage.

Copy Code code as follows:

<local:editcombobox myitemssource= "{Binding prolist,mode=twoway}" selecteditem= "{Binding Selpro,mode=twoway}" Selectedvaluepath= "Id" displaymemberpath= "Name"/>

Effect Demo

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