CC-Functions/Misc/Forms.cs

using System;
using System.Linq.Expressions;
using System.Reflection;
using System.Windows.Forms;

namespace CC_Functions.Misc
{
    public delegate void SetPropertyDelegate<TCtl, TProp>(TCtl control, Expression<Func<TCtl, TProp>> propexpr,
        TProp value) where TCtl : Control;

    public delegate TProp GetPropertyDelegate<TCtl, TProp>(TCtl control, Expression<Func<TProp>> propexpr)
        where TCtl : Control;

    public delegate void InvokeActionDelegate<TCtl>(TCtl control, Delegate dlg, params object[] args)
        where TCtl : Control;

    public delegate TResult InvokeFuncDelegate<TCtl, TResult>(TCtl control, Delegate dlg, params object[] args)
        where TCtl : Control;

    public static class Forms
    {
        public static void SetProperty<TCtl, TProp>(this TCtl control, Expression<Func<TCtl, TProp>> propexpr,
            TProp value) where TCtl : Control
        {
            if (control == null)
                throw new ArgumentNullException(nameof(control));

            if (propexpr == null)
                throw new ArgumentNullException(nameof(propexpr));
            if (control.InvokeRequired)
            {
                control.Invoke(new SetPropertyDelegate<TCtl, TProp>(SetProperty), control, propexpr, value);
                return;
            }

            MemberExpression propexprm = propexpr.Body as MemberExpression;
            if (propexprm == null)
                throw new ArgumentException("Invalid member expression.", nameof(propexpr));
            PropertyInfo prop = propexprm.Member as PropertyInfo;
            if (prop == null)
                throw new ArgumentException("Invalid property supplied.", nameof(propexpr));
            prop.SetValue(control, value);
        }

        public static TProp GetProperty<TCtl, TProp>(this TCtl control, Expression<Func<TProp>> propexpr)
            where TCtl : Control
        {
            if (control == null)
                throw new ArgumentNullException(nameof(control));
            if (propexpr == null)
                throw new ArgumentNullException(nameof(propexpr));
            if (control.InvokeRequired)
                return (TProp) control.Invoke(new GetPropertyDelegate<TCtl, TProp>(GetProperty), control, propexpr);
            MemberExpression propexprm = propexpr.Body as MemberExpression;
            if (propexprm == null)
                throw new ArgumentException("Invalid member expression.", nameof(propexpr));
            PropertyInfo prop = propexprm.Member as PropertyInfo;
            if (prop == null)
                throw new ArgumentException("Invalid property supplied.", nameof(propexpr));
            return (TProp) prop.GetValue(control);
        }

        public static void InvokeAction<TCtl>(this TCtl control, Delegate dlg, params object[] args)
            where TCtl : Control
        {
            if (control == null)
                throw new ArgumentNullException(nameof(control));
            if (dlg == null)
                throw new ArgumentNullException(nameof(dlg));
            if (control.InvokeRequired)
            {
                control.Invoke(new InvokeActionDelegate<TCtl>(InvokeAction), control, dlg, args);
                return;
            }

            dlg.DynamicInvoke(args);
        }

        public static TResult InvokeFunc<TCtl, TResult>(this TCtl control, Delegate dlg, params object[] args)
            where TCtl : Control
        {
            if (control == null)
                throw new ArgumentNullException(nameof(control));
            if (dlg == null)
                throw new ArgumentNullException(nameof(dlg));
            return control.InvokeRequired
                ? (TResult) control.Invoke(new InvokeFuncDelegate<TCtl, TResult>(InvokeFunc<TCtl, TResult>), control,
                    dlg, args)
                : (TResult) dlg.DynamicInvoke(args);
        }
    }
}