KJD/TEMUKJD/Extension/BindingExtensions.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Linq.Expressions;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace TemuKJD.Extension;

public class DataContext<TSource> : BindingSource
{
	public DataContext() { }
	public DataContext(TSource dataSource) : base(dataSource, null) { }

	// 强类型的 DataSource,避免调用方还要自己转型
	public new TSource DataSource
	{
		get => (TSource)base.DataSource;
		set => base.DataSource = value;
	}
}
public static class BindingExtensions
{


	/// <summary>
	/// TSource 必须显式指定（因为无法从参数推断），TControl 自动从调用方控件推断
	/// </summary>
	public static Binding Bind<TSource, TControl>(
		this TControl ctrl,
		DataContext<TSource> dataSource,
		Expression<Func<TControl, object>> controlPropertyExpr,
		Expression<Func<TSource, object>> dataPropertyExpr,
		DataSourceUpdateMode mode = DataSourceUpdateMode.OnPropertyChanged,
		string format = null,
		ConvertEventHandler parseHandler = null)
		where TControl : Control
	=> BindCore(ctrl, controlPropertyExpr.GetPropertyName(), dataSource, dataPropertyExpr, mode, format, parseHandler);

	public static Binding Bind<TControl>(
		this TControl ctrl,
		BindingSource dataSource,
		Expression<Func<TControl, object>> controlPropertyExpr,
		string dataPropertyName,
		DataSourceUpdateMode mode = DataSourceUpdateMode.OnPropertyChanged,
		string format = null,
		ConvertEventHandler parseHandler = null) where TControl : Control
	=> BindCore(ctrl, controlPropertyExpr.GetPropertyName(), dataSource, dataPropertyName, mode, format, parseHandler);

	// ---------- 共享的核心实现,不对外暴露 ----------
	private static Binding BindCore<TSource>(
		Control ctrl,
		string controlPropertyName,
		BindingSource bs,
		Expression<Func<TSource, object>> dataPropertyExpr,
		DataSourceUpdateMode mode,
		string format,
		ConvertEventHandler parseHandler) => BindCore(ctrl, controlPropertyName, bs, dataPropertyExpr.GetPropertyName(), mode, format, parseHandler);

	private static Binding BindCore(
		Control ctrl,
		string controlPropertyName,
		BindingSource bs,
		string dataPropertyName,
		DataSourceUpdateMode mode,
		string format,
		ConvertEventHandler parseHandler)
	{
		var binding = new Binding(controlPropertyName, bs, dataPropertyName, true, mode);

		if (!string.IsNullOrEmpty(format))
			binding.Format += (s, e) => e.Value = string.Format($"{{0:{format}}}", e.Value);

		if (parseHandler != null)
			binding.Parse += parseHandler;

		ctrl.DataBindings.Add(binding);
		return binding;
	}
	// ---------- TextBox ----------
	public static Binding Bind<TSource>(
		this TextBox ctrl,
		BindingSource bs,
		Expression<Func<TextBox, object>> controlPropertyExpr,
		Expression<Func<TSource, object>> dataPropertyExpr,
		DataSourceUpdateMode mode = DataSourceUpdateMode.OnPropertyChanged,
		string format = null,
		ConvertEventHandler parseHandler = null)
		=> BindCore(ctrl, controlPropertyExpr.GetPropertyName(), bs, dataPropertyExpr, mode, format, parseHandler);

	// ---------- CheckBox ----------
	public static Binding Bind<TSource>(
		this CheckBox ctrl,
		BindingSource bs,
		Expression<Func<CheckBox, object>> controlPropertyExpr,
		Expression<Func<TSource, object>> dataPropertyExpr,
		DataSourceUpdateMode mode = DataSourceUpdateMode.OnPropertyChanged,
		string format = null,
		ConvertEventHandler parseHandler = null)
		=> BindCore(ctrl, controlPropertyExpr.GetPropertyName(), bs, dataPropertyExpr, mode, format, parseHandler);

	// ---------- DateTimePicker ----------
	public static Binding Bind<TSource>(
		this DateTimePicker ctrl,
		BindingSource bs,
		Expression<Func<DateTimePicker, object>> controlPropertyExpr,
		Expression<Func<TSource, object>> dataPropertyExpr,
		DataSourceUpdateMode mode = DataSourceUpdateMode.OnPropertyChanged,
		string format = null,
		ConvertEventHandler parseHandler = null)
		=> BindCore(ctrl, controlPropertyExpr.GetPropertyName(), bs, dataPropertyExpr, mode, format, parseHandler);

	// ---------- ComboBox ----------
	public static Binding Bind<TSource>(
		this ComboBox ctrl,
		BindingSource bs,
		Expression<Func<ComboBox, object>> controlPropertyExpr,
		Expression<Func<TSource, object>> dataPropertyExpr,
		DataSourceUpdateMode mode = DataSourceUpdateMode.OnPropertyChanged,
		string format = null,
		ConvertEventHandler parseHandler = null)
		=> BindCore(ctrl, controlPropertyExpr.GetPropertyName(), bs, dataPropertyExpr, mode, format, parseHandler);

	// ---------- NumericUpDown ----------
	public static Binding Bind<TSource>(
		this NumericUpDown ctrl,
		BindingSource bs,
		Expression<Func<NumericUpDown, object>> controlPropertyExpr,
		Expression<Func<TSource, object>> dataPropertyExpr,
		DataSourceUpdateMode mode = DataSourceUpdateMode.OnPropertyChanged,
		string format = null,
		ConvertEventHandler parseHandler = null)
		=> BindCore(ctrl, controlPropertyExpr.GetPropertyName(), bs, dataPropertyExpr, mode, format, parseHandler);


	public static string GetPropertyName<TSource, TProperty>(
		this Expression<Func<TSource, TProperty>> propertyExpr)
	{
		if (propertyExpr.Body is MemberExpression member)
			return member.Member.Name;

		// 处理值类型属性被隐式转换为 object 的情况（如 decimal -> object）
		if (propertyExpr.Body is UnaryExpression unary &&
			unary.Operand is MemberExpression unaryMember)
			return unaryMember.Member.Name;

		throw new ArgumentException("表达式必须是形如 x => x.PropertyName 的属性访问", nameof(propertyExpr));
	}
}