Question

我在使用DataBinding到C＃中的复选框时遇到问题。复选框不反映其绑定到的对象的值。

我使用了“ checkBox1.DataBindings.Add（” Checked“，cb，” t“，false，DataSourceUpdateMode.OnPropertyChanged）”将简单的数据源绑定到对象cb。对象中的bool属性“ t”会根据复选框的选中状态进行更新，但是复选框的选中状态不反映对象的状态（cb.t）。

namespace WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        test cb = new test();
        public Form1()
        {
            InitializeComponent();

            cb.t = false;

            checkBox1.DataBindings.Add("Checked", cb, "t", false, DataSourceUpdateMode.OnPropertyChanged);
        }

        private void button1_Click(object sender, EventArgs e)
        {
            cb.t = true;
            //checkBox1.Refresh();
            //checkBox1.Invalidate();
        }
    }

    public class test
    {
        public bool t { set; get; }
    }
}

如果我单击button1，则复选框的状态不会更改；但是，如果我在窗体加载时在构造函数中设置cb.t = true，则复选框选中状态与cb.t的值相同。谢谢你的帮助。

Answer 1

属性更改时，不会通知您的视图更新。见- How To: INotifyPropertyChanged

尝试进行这些更改-

using System.ComponentModel;
using System.Runtime.CompilerServices;

public class test : INotifyPropertyChanged
    {
        private bool _t;
        public bool t {
            get { return _t; }
            set
            {
                if (value != _t)
                {
                    _t = value;
                    NotifyPropertyChanged();
                }
            }
        }


        public event PropertyChangedEventHandler PropertyChanged;

        // This method is called by the Set accessor of each property.
        // The CallerMemberName attribute that is applied to the optional propertyName
        // parameter causes the property name of the caller to be substituted as an argument.
        private void NotifyPropertyChanged([CallerMemberName] String propertyName = "")
        {
            if (PropertyChanged != null)
            {
                PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
            }
        }
    }

数据绑定到复选框无法正常工作

1 个答案: