C#从零开始学习(如何构建应用)(1)

开始使用 C#

本章所有的代码都放在
https://github.com/hikinazimi/head-first-Csharp

创建一个控制台应用

打开Visual Studio 2019 创建项目

选择控制台应用程序

创建后点击运行,就可以在控制台打印Hello World

构建一个游戏(创建WPF项目)

构建游戏的步骤

1. 首先创建WPF项目
2. 使用XAML构建窗口
3. 编写C#代码向这个窗口增加随机的动物表情符号
4. 允许用户成对的点击符号配对
5. 增加一个计时器

1.创建WPF项目

在MainWindow.xaml文件下打开工具箱

2.使用XAML构建窗口

在xaml文件下使用如下代码创建一个4*4方格的界面
Grid为网格的框架
TextBlock为显示的文字

<Window x:Class="MatchGame.MainWindow"xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"xmlns:d="http://schemas.microsoft.com/expression/blend/2008"xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"xmlns:local="clr-namespace:MatchGame"mc:Ignorable="d"Title="Find all of the matching animals" Height="450" Width="400"><Grid x:Name="mainGrid"><Grid.ColumnDefinitions><ColumnDefinition /><ColumnDefinition /><ColumnDefinition /><ColumnDefinition /></Grid.ColumnDefinitions><Grid.RowDefinitions><RowDefinition /><RowDefinition /><RowDefinition /><RowDefinition /><RowDefinition /></Grid.RowDefinitions><TextBlock Text="?" FontSize="36" HorizontalAlignment="Center" VerticalAlignment="Center" /><TextBlock Text="?" FontSize="36" HorizontalAlignment="Center" VerticalAlignment="Center" Grid.Column="1" /><TextBlock Text="?" FontSize="36" HorizontalAlignment="Center" VerticalAlignment="Center" Grid.Column="2"/><TextBlock Text="?" FontSize="36" HorizontalAlignment="Center" VerticalAlignment="Center" Grid.Column="3"/><TextBlock Text="?" FontSize="36" HorizontalAlignment="Center" VerticalAlignment="Center" Grid.Row="1" /><TextBlock Text="?" FontSize="36" Grid.Row="1" Grid.Column="1"HorizontalAlignment="Center" VerticalAlignment="Center" /><TextBlock Text="?" FontSize="36" Grid.Row="1" Grid.Column="2" HorizontalAlignment="Center" VerticalAlignment="Center" /><TextBlock Text="?" FontSize="36" Grid.Row="1" Grid.Column="3" HorizontalAlignment="Center" VerticalAlignment="Center"/><TextBlock Text="?" FontSize="36" Grid.Row="2" HorizontalAlignment="Center" VerticalAlignment="Center" /><TextBlock Text="?" FontSize="36" Grid.Row="2" Grid.Column="1" HorizontalAlignment="Center" VerticalAlignment="Center" /><TextBlock Text="?" FontSize="36" Grid.Row="2" Grid.Column="2" HorizontalAlignment="Center" VerticalAlignment="Center" /><TextBlock Text="?" FontSize="36" Grid.Row="2" Grid.Column="3" HorizontalAlignment="Center" VerticalAlignment="Center"/><TextBlock Text="?" FontSize="36" Grid.Row="3" HorizontalAlignment="Center" VerticalAlignment="Center" /><TextBlock Text="?" FontSize="36" Grid.Row="3" Grid.Column="1" HorizontalAlignment="Center" VerticalAlignment="Center" /><TextBlock Text="?" FontSize="36" Grid.Row="3" Grid.Column="2" HorizontalAlignment="Center" VerticalAlignment="Center" /><TextBlock Text="?" FontSize="36" Grid.Row="3" Grid.Column="3" HorizontalAlignment="Center" VerticalAlignment="Center" /><TextBlock x:Name="timeTextBlock" Text="Elapsed time" FontSize="36"HorizontalAlignment="Center" VerticalAlignment="Center"Grid.Row="4" Grid.ColumnSpan="4" /></Grid></Window>

打开.cs文件,这是程序逻辑代码实现的地方

3.编写C#代码向这个窗口增加随机的动物表情符号

然后再.cs文件下输入如下代码

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;namespace MatchGame
{/// <summary>/// MainWindow.xaml 的交互逻辑/// </summary>public partial class MainWindow : Window{public MainWindow(){InitializeComponent();SetUpGame();}private void SetUpGame(){List<string> animalEmoji = new List<string>()//创建表情列表{"😀","😀","😅", "😅","🍔","🍔","🍿", "🍿","🥩","🥩","🍠","🍠","😘", "😘","🚐", "🚐",};Random random = new Random();//mainGrid位xaml中grid的标签名,如<Grid x:Name="mainGrid">foreach (TextBlock textBlock in mainGrid.Children.OfType<TextBlock>()){int index = random.Next(animalEmoji.Count);string nextEmoji = animalEmoji[index];textBlock.Text = nextEmoji;animalEmoji.RemoveAt(index);}}}
}

然后我们就可以看到如下的界面

4.允许用户成对的点击符号配对

在textblock组件中MouseDown中添加如下函数

TextBlock lastTextBlockClicked;bool findingMatch = false;//跟踪是否只点击了一个private void TextBlock_MouseDown(object sender, MouseButtonEventArgs e){TextBlock textBlock = sender as TextBlock;if (findingMatch == false)//第一次选择{textBlock.Visibility = Visibility.Hidden;lastTextBlockClicked = textBlock;findingMatch = true;}else if (textBlock.Text == lastTextBlockClicked.Text){//第二次选择且相同matchesFound++;textBlock.Visibility = Visibility.Hidden;findingMatch = false;}else{//第二次选择且不同lastTextBlockClicked.Visibility = Visibility.Visible;findingMatch = false;}}

快速给所有xaml文件改MouseDown事件

将 /> 替换为 MouseDown=“TextBlock_MouseDown”/>

5. 增加一个计时器

首先在最上面的namespace下添加using System.Windows.Threading;
然后在添加如下代码

    public partial class MainWindow : Window{DispatcherTimer timer = new DispatcherTimer();int tenthsOfSecondsElapsed;//过去的时间int matchesFound;//找到的动物public MainWindow(){InitializeComponent();timer.Interval = TimeSpan.FromSeconds(.1);timer.Tick += Timer_Tick;SetUpGame();}private void Timer_Tick(object sender, EventArgs e){tenthsOfSecondsElapsed++;timeTextBlock.Text = (tenthsOfSecondsElapsed / 10F).ToString("0.0s");if(matchesFound==8){timer.Stop();timeTextBlock.Text = timeTextBlock.Text + " - end";}}

在xaml下添加一个新的textBlock
添加后有17个textBlock,导致数组越界,所以我们要使用if (textBlock.Name != “timeTextBlock”)判断

            foreach (TextBlock textBlock in mainGrid.Children.OfType<TextBlock>()){if (textBlock.Name != "timeTextBlock"){int index = random.Next(animalEmoji.Count);string nextEmoji = animalEmoji[index];textBlock.Text = nextEmoji;animalEmoji.RemoveAt(index);}}

最终结果如下

至此,我们就学习完了第一章,然后让我们复习一下本章讲了什么

• 学习了控制台的创建
• 学习了WPF的创建,以及一个简易游戏的实现
• xaml文件的简单应用
• 使用C#控制游戏逻辑的运行