Datagridview virtuelles Modell mit comboboxColumn

Question

ist es möglich, verschiedene Elemente in verschiedenen Reihen innerhalb eines comboboxcolumn in einem Datagridview zu haben. Dies würde mit virtuellem Modus. Codebeispiele wären toll.

Answer 1

Ich denke, was Sie suchen ist hier .

Die Technik beinhaltet die EditingControlShowing Ereignis des Datagridview Steuer Handhabung und die Datenquelle für die Aktualisierung DataGridViewComboBoxEditingControl (vermutlich auf der Grundlage der Werte in den anderen Spalten in der Zeile).

Edit: hier einige Code, der die wichtigsten Punkte

zeigt

//Some types we'll need
enum Jobs
{
    Programmer,
    Salesman
}

enum DrinkCode
{
    Coffee,
    Coke,
    MountainDew,
    GinAndTonic
}

internal class Drink
{
    public DrinkCode Code { get; set; }
    public string Name { get; set; }
    public bool Caffeinated { get; set; }
    public bool Alcoholic { get; set; }
}

internal class Person
{
    public string Name { get; set; }

    public Jobs Job { get; set; }

    public DrinkCode Drink { get; set; }
}

// the form class
public partial class Form1 : Form
{

    public Form1()
    {
        InitializeComponent();
    }

    private void Form1_Load(object sender, EventArgs e)
    {
        BindingSource bindingSource = new BindingSource();
        bindingSource.DataSource = FindPersons();
        this.dataGridView1.DataSource = bindingSource;

        DataGridViewComboBoxColumn column =
            new DataGridViewComboBoxColumn()
        {
            column.DataPropertyName = "Drink";
            column.HeaderText = "beverage";
            column.DisplayMember = "Name";
            column.ValueMember = "Code";
            column.DataSource = BuildDrinksList();
        }

       dataGridView1.Columns.Add(column);
       //handling this event is the nub of the solution
       dataGridView1.EditingControlShowing += 
           new DataGridViewEditingControlShowingEventHandler(dataGridView1_EditingControlShowing);
    }


    void dataGridView1_EditingControlShowing(object sender, DataGridViewEditingControlShowingEventArgs e)
    {
        //When the focus goes into the combo box cell, we can update the contents of the dropdown
        // 
        DataGridViewComboBoxEditingControl comboBox = e.Control as DataGridViewComboBoxEditingControl;
        //if you have more than one drop down this is not going to be good enough, but hey, it's an example!
        if (comboBox != null)
        {
            BindingSource bindingSource = this.dataGridView1.DataSource as BindingSource;
            Person person = bindingSource.Current as Person;
            BindingList<Drink> bindingList = t his.BuildDrinksList(person);
            comboBox.DataSource = bindingList;

        }
    }

    //the rest of this is just data to make the example work
    private BindingList<Drink> BuildDrinksList()
    {
        var drinks = new BindingList<Drink>();

        drinks.Add(new Drink() { Alcoholic = false, Caffeinated = true, Code = DrinkCode.Coffee, Name = "Coffee" });
        drinks.Add(new Drink() { Alcoholic = false, Caffeinated = true, Code = DrinkCode.Coke, Name = "Coke" });
        drinks.Add(new Drink() { Alcoholic = false, Caffeinated = true, Code = DrinkCode.MountainDew, Name = "Mountain Dew" });
        drinks.Add(new Drink() { Alcoholic = true, Caffeinated = false, Code = DrinkCode.GinAndTonic, Name = "Gin and Tonic" });

        return drinks;
    }

    private BindingList<Drink> BuildDrinksList(Person p)
    {
        var drinks = new BindingList<Drink>();

        if (p.Job == Jobs.Programmer)
        {
            drinks.Add(new Drink() { Alcoholic = false, Caffeinated = true, Code = DrinkCode.Coffee, Name = "Coffee" });
            drinks.Add(new Drink() { Alcoholic = false, Caffeinated = true, Code = DrinkCode.Coke, Name = "Coke" });
            drinks.Add(new Drink() { Alcoholic = false, Caffeinated = true, Code = DrinkCode.MountainDew, Name = "Mountain Dew" });
        }
        if (p.Job == Jobs.Salesman)
        {
            drinks.Add(new Drink() { Alcoholic = true, Caffeinated = false, Code = DrinkCode.GinAndTonic, Name = "Gin and Tonic" });
        }
        return drinks;
    }

    private BindingList<Person> FindPersons()
    {
        BindingList<Person> bindingList = new BindingList<Person>();
        bindingList.Add(new Person() { Job = Jobs.Programmer, Drink = DrinkCode.Coffee, Name = "steve" });
        bindingList.Add(new Person() { Job = Jobs.Salesman, Drink = DrinkCode.GinAndTonic, Name = "john" });
        return bindingList;
    }
}