动态生成的文本框

Question

我需要一种动态创建多个文本框并访问它们的值的方法。

在我的表单中，用户输入一个 1 到 50 之间的数字，然后必须使用动态名称创建该数量的文本框，即成分 1、成分 2、成分 3、...成分 50 等。

我有一个 for 循环，它将使用该值创建多个文本框，但是如何将文本框值存储在字符串变量中？

这是当前为空的 for 循环

int i = Form1.ingredientCount;

for (i = 1; i < Form1.ingredientCount; i++)
{
    //create new text box
    //create new string that then holds value from text box
}

澄清：

用户在上一页输入一个数字。

然后这个数字决定了创建的文本框的数量和创建的字符串的数量。

文本框和字符串需要在 for 循环中具有唯一生成的 ID。

我还需要另一个文本框来显示每种成分的重量，尽管我自己可以弄清楚。

所以基本上我希望每个文本框和字符串都被命名为

"input" + i（其中 i 是增量器） 这样名字就会变成“input1”、“input2”、“input3”等等。

与包含文本框中数据的字符串相同。

Answer 1

我以为我会编辑它，因为我似乎误解了这个问题

您可以将其绑定为如下形式：

public partial class Form1 : Form
{
    Recepie pancakes = new Recepie();
    IList<UniqueHolder> items = new List<UniqueHolder>();

    public Form1()
    {
        InitializeComponent();
        pancakes.Ingredients.Add(new Ingredient { Title = "Milk - 250 gr" });
        pancakes.Ingredients.Add(new Ingredient { Title = "Butter - 25 gr" });
        pancakes.Ingredients.Add(new Ingredient { Title = "Oil - 1 large spoon" });
        pancakes.Ingredients.Add(new Ingredient { Title = "Sugar - 100 gr" });
        pancakes.Ingredients.Add(new Ingredient { Title = "Flower - 200 gr" });
    }

    private void Form1_Load(object sender, EventArgs e)
    {

    }

    private void button1_Click(object sender, EventArgs e)
    {
        for (var i = 0; i < pancakes.Ingredients.Count; i++)
        {
            Ingredient ing = pancakes.Ingredients[i];
            TextBox tb = new TextBox { Location = new Point(10, i * 30), Size = new Size(200, 20), Text = ing.Title };
            UniqueHolder uh = new UniqueHolder { Ingredient = ing, TextBox = tb };
            this.Controls.Add(tb);
        }
    }
}

唯一的持有者对成分或文本框的变化进行数据绑定

public class UniqueHolder : IDisposable
{
    public Guid UniqueID { get; set; }

    public override bool Equals(object obj)
    {
        if (obj is UniqueHolder)
        {

            return Guid.Equals(((UniqueHolder)obj).UniqueID, this.UniqueID);
        }
        return base.Equals(obj);
    }

    public override int GetHashCode()
    {
        return UniqueID.GetHashCode();
    }

    private TextBox textbox;
    public TextBox TextBox
    {
        get
        {
            return textbox;
        }
        set
        {
            if (object.Equals(textbox, value))
            {
                return;
            }
            if (textbox != null)
            {
                textbox.TextChanged -= OnTextChanged;
            }
            textbox = value;
            if (textbox != null)
            {
                textbox.TextChanged += OnTextChanged;
            }
        }
    }

    private Ingredient ingredient;
    public Ingredient Ingredient 
    {
        get
        {
            return ingredient;
        }
        set
        {
            if (object.Equals(ingredient, value))
            {
                return;
            }
            if (ingredient != null)
            {
                ingredient.PropertyChanged -= OnIngredientChanged;
            }
            ingredient = value;
            if (ingredient != null)
            {
                ingredient.PropertyChanged += OnIngredientChanged;
            }
        }
    }

    public UniqueHolder()
    {
        this.UniqueID = Guid.NewGuid();
    }

    protected virtual void OnIngredientChanged(object sender, PropertyChangedEventArgs e)
    {
        if (string.Equals(e.PropertyName, "Title", StringComparison.OrdinalIgnoreCase))
        {
            if (TextBox == null)
            {
                return;
            }
            TextBox.Text = Ingredient.Title;
        }
    }

    protected virtual void OnTextChanged(object sender, EventArgs e)
    {
        var tb = sender as TextBox;
        if (tb == null)
        {
            return;
        }
        if (Ingredient == null)
        {
            return;
        }
        Ingredient.Title = tb.Text;
    }

    public void Dispose()
    {
        Ingredient = null;
        TextBox = null;
    }
}

您可以使用这些成分回到接收器

public class Recepie : IDisposable
{
    private readonly IList<Ingredient> ingredients = new ObservableCollection<Ingredient>();
    public IList<Ingredient> Ingredients
    {
        get
        {
            return ingredients;
        }
    }

    protected virtual void OnIngredientsListChanged(object sender, NotifyCollectionChangedEventArgs e)
    {
        if (e.OldItems != null)
        {
            foreach (var item in e.OldItems)
            {
                var ing = item as Ingredient;
                if (ing == null)
                {
                    continue;
                }
                ing.Recepie = null;
            }
        }
        if (e.NewItems != null)
        {
            foreach (var item in e.NewItems)
            {
                var ing = item as Ingredient;
                if (ing == null)
                {
                    continue;
                }
                ing.Recepie = this;
            }
        }
    }

    public Recepie()
    {
        var obs = Ingredients as INotifyCollectionChanged;
        if (obs != null)
        {
            obs.CollectionChanged += OnIngredientsListChanged;
        }
    }

    public void Dispose()
    {
        int total = Ingredients.Count;
        for (int i = total; --i >= 0; )
        {
            Ingredients.RemoveAt(i);
        }
        var obs = Ingredients as INotifyCollectionChanged;
        if (obs != null)
        {
            obs.CollectionChanged -= OnIngredientsListChanged;
        }
    }
}

public class Ingredient : INotifyPropertyChanged
{
    public event PropertyChangedEventHandler PropertyChanged;

    private Recepie recepie;
    public virtual Recepie Recepie
    {
        get
        {
            return recepie;
        }
        set
        {
            if (object.Equals(recepie, value))
            {
                return;
            }
            recepie = value;
            RaisePropertyChanged("Recepie");
        }
    }

    private string title;
    public string Title
    {
        get
        {
            return title;
        }
        set
        {
            if (string.Equals(title, value))
            {
                return;
            }
            title = value;
            RaisePropertyChanged("Title");
        }
    }

    protected virtual void RaisePropertyChanged(string propertyName)
    {
        var local = PropertyChanged;
        if (local != null)
        {
            local.Invoke(this, new PropertyChangedEventArgs(propertyName));
        }
    }
}

Answer 2

与其创建一个字符串来保存文本框中的值，不如将文本框保存在一个列表中，并在需要时从 Text 属性中获取值：这样就不需要连接 TextChanged 事件等。编辑：您不需要字符串变量来存储文本框文本，因为您现在可以在需要时通过列表和 Text 属性对其进行引用。

// a field 
List<TextBox> ingredientTextBoxes = new List<TextBox>();

private void Populate(int ingredientCount)
{
    for (i = 1; i < ingredientCount; i++)
    {
        // Assign a consecutive name so can order by it
        TextBox tb = new TextBox { Name = "IngredientTextbox" + i};
        ingredientTextBoxes.Add(tb);
    }
}

// when you want the ingredients
public List<string> GetIngredients
{
    List<string> ingredients = new List<string>();

    foreach (var tb in ingredientTextBoxes)
    {
        ingredients.Add(tb.text);
    }

    return ingredients;
}

// contains
private List<string> GetIngredientsMatching(string match)
{
    // Contains really should take a StringComparison parameter, but it doesn't
    return ingredientTextBoxes
                    .Where(t => t.Text.ToUpper().Contains(match.ToUpper()))
                    .Select(t => t.Text);
}

编辑：如果您要为每种成分设置多个值，则使用用户控件公开您想要的属性 - 总结数量、重量、描述（例如“一小撮”盐） - 以最方便的方式访问这些属性的代码。