//DelegateCommand(命令绑定类,实现:ICommand接口)
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Input;
namespace WpfMVVM.Commands
{
class DelegateCommand:ICommand
{
public bool CanExecute(object parameter)
{
if (this.CanExecuteFunc==null)
{
return true;
}
return this.CanExecuteFunc(parameter);
}
public void Execute(object parameter)
{
if (this.ExecuteAction==null)
{
return;
}
this.ExecuteAction(parameter);
}
public Func<object,bool> CanExecuteFunc { get; set; }//Func是一个委托,第一个类型是参数类型,第二个类型是返回值类型
public Action<object> ExecuteAction { get; set; }//Acton也是一个委托,但他没有返回值,里面类型是参数的类型
public event EventHandler CanExecuteChanged;
}
}
//ViewModel基类(实现INotifyPropertyChanged接口,VeiwModel类继承该类,也可以ViewModel直接是实现该接口也可以)
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.ComponentModel;
namespace WpfMVVM.ViewModels
{
class NotificationObject : INotifyPropertyChanged
{
public event PropertyChangedEventHandler PropertyChanged;
public void RaisePropertyChanged(string propertyName)
{
if (this.PropertyChanged != null)
{
this.PropertyChanged.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
}
}
}
//ViewModel类
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Microsoft.Win32;
using WpfMVVM.Commands;
namespace WpfMVVM.ViewModels
{
class ViewModelMainClass : NotificationObject
{
private double input1;
public double Input1
{
get { return input1; }
set
{
input1 = value;
this.RaisePropertyChanged("Input1");
}
}
private double input2;
public double Input2
{
get { return input2; }
set
{
input2 = value;
this.RaisePropertyChanged("Input2");
}
}
private double result;
public double Result
{
get { return result; }
set
{
result = value;
this.RaisePropertyChanged("Result");
}
}
public DelegateCommand AddCommand { get; set; }
private void Add(object parameter)
{
this.Result = this.Input1 + this.Input2;
}
public ViewModelMainClass()
{
this.AddCommand = new DelegateCommand();
this.AddCommand.ExecuteAction=new Action<object>(this.Add);
}
}
}
//xaml代码
<Grid>
<TextBox Text="{Binding Input1}" x:Name="tb1" Height="60" Background="LemonChiffon" Margin="10,0,10,240"/>
<TextBox Text="{Binding Input2}" x:Name="tb2" Height="60" Background="LemonChiffon" Margin="10,70,10,180" />
<TextBox Text="{Binding Result}" x:Name="tb3" Height="60" Background="LemonChiffon" Margin="10,140,10,120"/>
<Button x:Name="bt1" Command="{Binding AddCommand}" Margin="0,240,0,0">Add</Button>
</Grid>