Winforms ComboBox에서 항목의 텍스트를 동적으로 변경합니다.

Question

사용자 지정 클래스의 인스턴스를 포함하는 Winforms ComboBox이 있습니다. 항목이 ComboBox의 Items 컬렉션에 처음 추가되면 ToString 메서드는 각 메서드를 호출합니다.

그러나 사용자가 응용 프로그램이 실행되는 언어를 변경하면 ToString 메서드의 결과가 변경됩니다.

따라서 ComboBox에서 모든 항목을 제거하지 않고 다시 모든 항목에 대해 ToString 메서드를 호출하여 다시 호출 할 수 있습니까?

Answer 1

감사합니다, RefreshItems() 작업을 서브 클래스) 그러나 나는 당신이 내가

했다, 여기에 포함 된 Combro 상자를 서브 클래 싱 할 수 없기 때문에 조금 더 열심히했다, 난 그냥되는 ToolStripComboBox에 대해 동일한 작업을 수행해야했다

public class RefreshingComboBox : ComboBox 
{ 
    public new void RefreshItem(int index) 
    { 
     base.RefreshItem(index); 
    } 

    public new void RefreshItems() 
    { 
     base.RefreshItems(); 
    } 
} 

을해야했다

public class RefreshingToolStripComboBox : ToolStripComboBox 
{ 
    // We do not want "fake" selectedIndex change events etc, subclass that overide the OnIndexChanged etc 
    // will have to check InOnCultureChanged them selfs 
    private bool inRefresh = false; 
    public bool InRefresh { get { return inRefresh; } } 

    public void Refresh() 
    { 
     try 
     { 
      inRefresh = true; 

      // This is harder then it shold be, as I can't get to the Refesh method that 
      // is on the embebed combro box. 
      // 
      // I am trying to get ToString recalled on all the items 
      int selectedIndex = SelectedIndex; 
      object[] items = new object[Items.Count]; 
      Items.CopyTo(items, 0); 

      Items.Clear(); 

      Items.AddRange(items); 
      SelectedIndex = selectedIndex; 
     } 
     finally 
     { 
      inRefresh = false; 
     } 
    } 

    protected override void OnSelectedIndexChanged(EventArgs e) 
    { 
     if (!inRefresh) 
     { 
      base.OnSelectedIndexChanged(e); 
     } 
    } 
} 

나는 코드가 내가 여기에 포함되지 않은 ToolStripComboBox의 경우와 동일로, OnSelectedValueChanged, OnSelectedItemChanged 및 OnSelectedIndexChanged를 재정 의하여 정상 CombroBox에 대한 원치 않는 이벤트를 중지 같은 여행을해야했다.

Answer 2

RefreshItems() 메서드를 호출하여이 작업을 수행 할 수 있어야합니다.

Answer 3

svick이 맞습니다. 그러나 Ian Ringrose에 언급 된 것처럼 하위 클래스가 필요합니다. RefreshItems는 System.Windows.Forms.ComboBox의 보호 된 메서드입니다.

A는 응용 프로그램이 아래의 문제의 예를 제공 양식 및 RefreshItems 방법은 콤보 업데이트 : 그렇게 만 호출 할 수 있습니다 (이 보호 그러나 같은 svick

using System; 
using System.Collections.Generic; 
using System.ComponentModel; 
using System.Data; 
using System.Drawing; 
using System.Text; 
using System.Windows.Forms; 

namespace WindowsApplication1 
{ 
    public class Form1 : Form 
    { 
     private List<HelloWorld> helloWorlds; 

     #region Form1.Designer.cs 
     /// <summary> 
     /// Required designer variable. 
     /// </summary> 
     private System.ComponentModel.IContainer components = null; 

     /// <summary> 
     /// Clean up any resources being used. 
     /// </summary> 
     /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param> 
     protected override void Dispose(bool disposing) 
     { 
      if (disposing && (components != null)) 
      { 
       components.Dispose(); 
      } 
      base.Dispose(disposing); 
     } 

     #region Windows Form Designer generated code 

     /// <summary> 
     /// Required method for Designer support - do not modify 
     /// the contents of this method with the code editor. 
     /// </summary> 
     private void InitializeComponent() 
     { 
      this.comboBox1 = new RefreshingComboBox(); 
      this.comboBox2 = new RefreshingComboBox(); 
      this.label1 = new System.Windows.Forms.Label(); 
      this.label2 = new System.Windows.Forms.Label(); 
      this.button1 = new System.Windows.Forms.Button(); 
      this.button2 = new System.Windows.Forms.Button(); 
      this.button3 = new System.Windows.Forms.Button(); 
      this.SuspendLayout(); 
      // 
      // comboBox1 
      // 
      this.comboBox1.FormattingEnabled = true; 
      this.comboBox1.Location = new System.Drawing.Point(76, 12); 
      this.comboBox1.Name = "comboBox1"; 
      this.comboBox1.Size = new System.Drawing.Size(115, 21); 
      this.comboBox1.TabIndex = 0; 
      // 
      // comboBox2 
      // 
      this.comboBox2.FormattingEnabled = true; 
      this.comboBox2.Location = new System.Drawing.Point(250, 12); 
      this.comboBox2.Name = "comboBox2"; 
      this.comboBox2.Size = new System.Drawing.Size(218, 21); 
      this.comboBox2.TabIndex = 1; 
      // 
      // label1 
      // 
      this.label1.AutoSize = true; 
      this.label1.Location = new System.Drawing.Point(12, 15); 
      this.label1.Name = "label1"; 
      this.label1.Size = new System.Drawing.Size(58, 13); 
      this.label1.TabIndex = 2; 
      this.label1.Text = "Language:"; 
      // 
      // label2 
      // 
      this.label2.AutoSize = true; 
      this.label2.Location = new System.Drawing.Point(213, 15); 
      this.label2.Name = "label2"; 
      this.label2.Size = new System.Drawing.Size(31, 13); 
      this.label2.TabIndex = 3; 
      this.label2.Text = "Text:"; 
      // 
      // button1 
      // 
      this.button1.Location = new System.Drawing.Point(34, 42); 
      this.button1.Name = "button1"; 
      this.button1.Size = new System.Drawing.Size(75, 23); 
      this.button1.TabIndex = 4; 
      this.button1.Text = "Set All"; 
      this.button1.UseVisualStyleBackColor = true; 
      this.button1.Click += new System.EventHandler(this.button1_Click); 
      // 
      // button2 
      // 
      this.button2.Location = new System.Drawing.Point(116, 42); 
      this.button2.Name = "button2"; 
      this.button2.Size = new System.Drawing.Size(75, 23); 
      this.button2.TabIndex = 5; 
      this.button2.Text = "Set Random"; 
      this.button2.UseVisualStyleBackColor = true; 
      this.button2.Click += new System.EventHandler(this.button2_Click); 
      // 
      // button3 
      // 
      this.button3.Location = new System.Drawing.Point(393, 42); 
      this.button3.Name = "button3"; 
      this.button3.Size = new System.Drawing.Size(75, 23); 
      this.button3.TabIndex = 6; 
      this.button3.Text = "Refresh!"; 
      this.button3.UseVisualStyleBackColor = true; 
      this.button3.Click += new System.EventHandler(this.button3_Click); 
      // 
      // Form1 
      // 
      this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F); 
      this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font; 
      this.ClientSize = new System.Drawing.Size(556, 77); 
      this.Controls.Add(this.button3); 
      this.Controls.Add(this.button2); 
      this.Controls.Add(this.button1); 
      this.Controls.Add(this.label2); 
      this.Controls.Add(this.label1); 
      this.Controls.Add(this.comboBox2); 
      this.Controls.Add(this.comboBox1); 
      this.Name = "Form1"; 
      this.Text = "Form1"; 
      this.ResumeLayout(false); 
      this.PerformLayout(); 

     } 

     #endregion 

     private System.Windows.Forms.ComboBox comboBox1; 
     private System.Windows.Forms.ComboBox comboBox2; 
     private System.Windows.Forms.Label label1; 
     private System.Windows.Forms.Label label2; 
     private System.Windows.Forms.Button button1; 
     private System.Windows.Forms.Button button2; 
     private System.Windows.Forms.Button button3; 

     #endregion 

     public Form1() 
     { 
      InitializeComponent(); 

      comboBox1.DataSource = new HelloWorld().GetLanguages(); 

      helloWorlds = new List<HelloWorld>(); 
      while (helloWorlds.Count < 10) 
      { 
       helloWorlds.Add(new HelloWorld()); 
      } 

      comboBox2.DataSource = helloWorlds; 
     } 

     [STAThread] 
     static void Main() 
     { 
      Application.EnableVisualStyles(); 
      Application.SetCompatibleTextRenderingDefault(false); 
      Application.Run(new Form1()); 
     } 

     private void changeAllLanguages() 
     { 
      HelloWorld.LanguageValue newLang = (HelloWorld.LanguageValue) comboBox1.SelectedValue; 

      helloWorlds.ForEach(
       delegate(HelloWorld hw) 
       { 
        hw.Language = newLang; 
       }); 

     } 

     private void changeRandomLanguage() 
     { 
      int index = new Random().Next(helloWorlds.Count); 
      HelloWorld.LanguageValue newLang = (HelloWorld.LanguageValue) comboBox1.SelectedValue; 

      helloWorlds[index].Language = newLang; 
     } 

     private void button1_Click(object sender, EventArgs e) 
     { 
      changeAllLanguages(); 
     } 

     private void button2_Click(object sender, EventArgs e) 
     { 
      changeRandomLanguage(); 
     } 

     private void button3_Click(object sender, EventArgs e) 
     { 
      (comboBox2 as RefreshingComboBox).RefreshItems(); 
     } 
    } 

    public class RefreshingComboBox : System.Windows.Forms.ComboBox 
    { 
     public new void RefreshItem(int index) 
     { 
      base.RefreshItem(index); 
     } 

     public new void RefreshItems() 
     { 
      base.RefreshItems(); 
     } 
    } 

    public class HelloWorld 
    { 
     public enum LanguageValue 
     { 
      English, 
      日本語, 
      Deutsch, 
      Français, 
      Český 
     } 

     private LanguageValue language; 

     public LanguageValue Language 
     { 
      get 
      { 
       return language; 
      } 
      set 
      { 
       language = value; 
      } 
     } 

     public Array GetLanguages() 
     { 
      return Enum.GetValues(typeof(LanguageValue)); 
     } 

     Dictionary<LanguageValue, string> helloWorlds; 

     public HelloWorld() 
     { 
      helloWorlds = new Dictionary<LanguageValue, string>(); 
      helloWorlds[LanguageValue.English] = "Hello, world!"; 
      helloWorlds[LanguageValue.日本語] = "こんにちは、世界！"; 
      helloWorlds[LanguageValue.Deutsch] = "Hallo, Welt!"; 
      helloWorlds[LanguageValue.Français] = "Sallut, monde!"; 
      helloWorlds[LanguageValue.Český] = "Ahoj svět!"; 
     } 

     public override string ToString() 
     { 
      return helloWorlds[language]; 
     } 
    } 
} 

Answer 4

나는이 확장 사용 : 나는 정확히 같은 상황이 있었다

 /// <summary> 
     /// Recreates the items 
     /// </summary> 
     public static void RefreshItems(this ComboBox cb) 
     { 
      var selectedIndex = cb.SelectedIndex; 
      cb.SelectedIndex = -1;    
      MethodInfo dynMethod = cb.GetType().GetMethod("RefreshItems", BindingFlags.NonPublic | BindingFlags.Instance); 
      dynMethod.Invoke(cb, null); 
      cb.SelectedIndex = selectedIndex; 

     }