如何在 Winforms 桌面应用程序中制作自动完成文本框

Posted 2023-03-05

【中文标题】如何在 Winforms 桌面应用程序中制作自动完成文本框

【英文标题】：How to make an auto-complete textbox in a winforms desktop application

【发布时间】：2011-06-05 12:29:04

【问题描述】：

我有一个单词列表。该列表包含大约 100-200 个文本字符串（实际上是地铁站的名称）。

我想制作一个自动完成的文本框。例如，用户按下“N”字母，然后出现一个（结束）适当的选项（只有一个选项）。必须选择结局。

怎么做？

PS1：我猜，有一个带有如下属性的文本框控件：

List<string> AppropriateOptions/* ... */

PS2：对不起我的英语。如果你不明白 -> 问我，我会尽力解释！

【参考方案1】：

以防万一@leniel 的链接失效，这里有一些代码可以解决问题：

AutoCompleteStringCollection allowedTypes = new AutoCompleteStringCollection();
allowedTypes.AddRange(yourArrayOfSuggestions);
txtType.AutoCompleteCustomSource = allowedTypes;
txtType.AutoCompleteMode = AutoCompleteMode.Suggest;
txtType.AutoCompleteSource = AutoCompleteSource.CustomSource;

【讨论】：

谢谢乔尔，它对我有用。我们可以用向上和向下箭头键选择建议文本吗？我试过但它不允许我。

@rakesh 我已经有一段时间没有在 winforms 上工作了，我不记得是“标准”功能还是需要额外的努力。对不起

感谢您提供要点而不是仅提供链接的答案。

【参考方案2】：

使用组合框而不是文本框。以下示例将自动完成，匹配任何一段文本，而不仅仅是起始字母。

这应该是一个完整的表格，只需添加您自己的数据源，以及数据源列名。 :-)

using System;
using System.Data;
using System.Windows.Forms;

public partial class frmTestAutocomplete : Form


    private DataTable maoCompleteList;
    private const string MC_DISPLAY_COL = "name";
    private const string MC_ID_COL = "id";

    public frmTestAutocomplete()
    
        InitializeComponent();
    

    private void frmTestAutocomplete_Load(object sender, EventArgs e)
    

        maoCompleteList = oData.PurificationRuns;
        maoCompleteList.CaseSensitive = false; //turn off case sensitivity for searching

        testCombo.DisplayMember = MC_DISPLAY_COL;
        testCombo.ValueMember = MC_ID_COL;
        testCombo.DataSource = GetDataTableFromDatabase();
        testCombo.SelectedIndexChanged += testCombo_SelectedIndexChanged;
        testCombo.KeyUp += testCombo_KeyUp;
    


    private void testCombo_KeyUp(object sender, KeyEventArgs e)
    
        //use keyUp event, as text changed traps too many other evengts.

        ComboBox oBox = (ComboBox)sender;
        string sBoxText = oBox.Text;

        DataRow[] oFilteredRows = maoCompleteList.Select(MC_DISPLAY_COL + " Like '%" + sBoxText + "%'");

        DataTable oFilteredDT = oFilteredRows.Length > 0
                                ? oFilteredRows.CopyToDataTable()
                                : maoCompleteList;

        //NOW THAT WE HAVE OUR FILTERED LIST, WE NEED TO RE-BIND IT WIHOUT CHANGING THE TEXT IN THE ComboBox.

        //1).UNREGISTER THE SELECTED EVENT BEFORE RE-BINDING, b/c IT TRIGGERS ON BIND.
        testCombo.SelectedIndexChanged -= testCombo_SelectedIndexChanged; //don't select on typing.
        oBox.DataSource = oFilteredDT; //2).rebind to filtered list.
        testCombo.SelectedIndexChanged += testCombo_SelectedIndexChanged;


        //3).show the user the new filtered list.
        oBox.DroppedDown = true; //this will overwrite the text in the ComboBox, so 4&5 put it back.

        //4).binding data source erases text, so now we need to put the user's text back,
        oBox.Text = sBoxText;
        oBox.SelectionStart = sBoxText.Length; //5). need to put the user's cursor back where it was.


    

    private void testCombo_SelectedIndexChanged(object sender, EventArgs e)
    

        ComboBox oBox = (ComboBox)sender;

        if (oBox.SelectedValue != null)
        
            MessageBox.Show(string.Format(@"Item #0 was selected.", oBox.SelectedValue));
        
    



//=====================================================================================================
//      code from frmTestAutocomplete.Designer.cs
//=====================================================================================================
partial class frmTestAutocomplete


    /// <summary>
    /// Required designer variable.
    /// </summary>
    private readonly 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.testCombo = new System.Windows.Forms.ComboBox();
        this.SuspendLayout();
        // 
        // testCombo
        // 
        this.testCombo.FormattingEnabled = true;
        this.testCombo.Location = new System.Drawing.Point(27, 51);
        this.testCombo.Name = "testCombo";
        this.testCombo.Size = new System.Drawing.Size(224, 21);
        this.testCombo.TabIndex = 0;
        // 
        // frmTestAutocomplete
        // 
        this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
        this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
        this.ClientSize = new System.Drawing.Size(292, 273);
        this.Controls.Add(this.testCombo);
        this.Name = "frmTestAutocomplete";
        this.Text = "frmTestAutocomplete";
        this.Load += new System.EventHandler(this.frmTestAutocomplete_Load);
        this.ResumeLayout(false);

    

    #endregion

    private System.Windows.Forms.ComboBox testCombo;

【参考方案3】：

Leniel 的答案链接在 vb.net，感谢 Joel 的输入。提供我的代码以使其更明确：

private void InitializeTextBox()


    AutoCompleteStringCollection allowedStatorTypes = new AutoCompleteStringCollection();
    var allstatortypes = StatorTypeDAL.LoadList<List<StatorType>>().OrderBy(x => x.Name).Select(x => x.Name).Distinct().ToList();

    if (allstatortypes != null && allstatortypes.Count > 0)
    
        foreach (string item in allstatortypes)
        
            allowedStatorTypes.Add(item);
        
    

    txtStatorTypes.AutoCompleteMode = AutoCompleteMode.Suggest;
    txtStatorTypes.AutoCompleteSource = AutoCompleteSource.CustomSource;
    txtStatorTypes.AutoCompleteCustomSource = allowedStatorTypes;

【参考方案4】：

使用组合框，设置其数据源或提供硬编码条目，但设置以下属性：

    AutoCompleteMode = Suggest;
    AutoCompleteSource = ListItems;

【参考方案5】：

您希望将TextBox.AutoCompleteSource 设置为CustomSource，然后将所有字符串添加到其AutoCompleteCustomSource 属性，即StringCollection。那你应该很高兴了。

【参考方案6】：

我想补充一点，TextBox 的标准自动完成功能只能从字符串的开头开始工作，所以如果你点击 N，只会找到以 N 开头的字符串。如果您想要更好的东西，您必须使用一些不同的控件或自己实现行为（即使用一些计时器对 TextChanged 事件做出反应以延迟执行，而不是使用 IndexOf(inputString) 过滤您的令牌列表搜索，然后将您的 AutoCompleteSource 设置为过滤后的列表。