使用组合框 c# 在图片框中显示图像答案

【问题标题】：Display Image in Picture Box Using Combo Box c#使用组合框 c# 在图片框中显示图像
【发布时间】：2021-12-13 07:58:18
【问题描述】：

我正在尝试在 C# 中创建一个电影票务系统，如果用户在组合框中选择一部电影，则该电影的海报应该显示在图片框中。我试过这段代码，但我的问题是组合框中的选择是图像的路径，选择应该是电影标题而不是图像的路径。

 private void Form1_Load(object sender, EventArgs e)
    {
        string[] imgs = Directory.GetFiles(@"C:\Users\me\Documents\C# program\Poster");
        foreach(string file in imgs)
        {
            comboBox1.Items.Add(file);
        }
    }

    private void comboBox1_SelectedIndexChanged(object sender, EventArgs e)
    {
        string s = comboBox1.SelectedItem.ToString();
        pictureBox1.Image = new Bitmap(s);

如何使用带有电影标题的组合框显示电影海报？

【问题讨论】：

请检查答案并验证。

标签： c# combobox picturebox

【解决方案1】：

试试这个：

pictureBox1.Image = Image.FromFile(YourImagePathInStringMode);

【讨论】：

【解决方案2】：

如果我正确阅读了您的问题，那么现在您有一个图片框，可以正确显示从组合框中选择的海报图像，而您遇到的问题是您希望组合框的内容是 电影的标题而不是海报的位置。

根据程序的设置方式，最简单的回答方法可能是保存 Form1_Load 函数中的字符串数组，创建电影标题列表，并将其用作组合框项的来源。

如果您使用的是一组预定义的电影标题，这应该很容易，但如果您不提前知道电影的内容可能会很棘手 - 如果可能的话，您可以将它们用作海报图像文件名，并为您的 Form1_Load 函数提供类似的内容：

 private string[] posterPaths;
 
 private void Form1_Load(object sender, EventArgs e)
  {
   posterPaths = Directory.GetFiles(@"C:\Users\me\Documents\C#program\Poster");
   foreach(string file in posterPaths)
    {
     //find where the name of the image is in the path
     int index = file.LastIndexOf('\');
     //remove the parts that aren't the movie's name
     string movieName = file.Substring(index,file.Length-index-4)
     comboBox1.Items.Add(movieName);
    }
  }

然后您可以使用 comboBox.SelectedIndex 属性来确定要为 imageBox 使用的路径。

【讨论】：

【解决方案3】：

全局定义图片路径，

private const string imagePath = @"C:\Users\sachithw\Desktop\bikes";

但通过添加App.Config 文件并从那里读取路径，它更易于配置。

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
    <appSettings>
      <add key="imagePath" value="C:\Users\sachithw\Desktop\bikes" />
    </appSettings>
</configuration>

你可以读取路径如下

string imagePath = System.Configuration.ConfigurationManager.AppSettings["imagePath"].ToString();

完整代码，

public partial class Form1: Form {
  private
  const string imagePath = @ "C:\Users\sachithw\Desktop\bikes";
  //string imagePath = System.Configuration.ConfigurationManager.AppSettings["imagePath"].ToString();

  public Form1() {

    this.BackgroundImageLayout = ImageLayout.Stretch;
    InitializeComponent();
  }

  private void Form1_Load(object sender, EventArgs e) {
    DirectoryInfo di = new DirectoryInfo(imagePath);
    FileInfo[] files = di.GetFiles("*.jpg");
    foreach(FileInfo file in files) {
      comboBox1.Items.Add(file.Name);
    }
  }

  private void comboBox1_SelectedIndexChanged(object sender, EventArgs e) {
    string fileName = comboBox1.SelectedItem.ToString();
    if (pictureBox1.Image != null && pictureBox1 != null) {
      pictureBox1.Image.Dispose();
    }
    string imageFullPath = imagePath + "\\" + fileName;

    pictureBox1.Image = Image.FromFile(imageFullPath);
  }
}

请务必处理图片框中的前一张图片，因为您在 PictureBox 中使用多个图像。否则会抛出'System.OutOfMemoryException' 异常。

【讨论】：

【解决方案4】：

以下依赖于存储每部电影的标题和图像的 json 文件。

此处完成的 json 文件位于包含电影图像的文件夹中，但可以位于任何适合您的文件夹中。

我使用可用图像的 Json 文件）

[
  {
    "Title": "Movie 1",
    "ImageName": "checkmark.png"
  },
  {
    "Title": "Movie 2",
    "ImageName": "Mail_16x.png"
  },
  {
    "Title": "Movie 3",
    "ImageName": "upGreenArrow.png"
  }
]

电影课

namespace MoviesCodeSample
{
    /// <summary>
    /// Represents a single movie, add other
    /// properties if needed before serializing
    /// data in MovieOperations.
    /// </summary>
    public class Movie
    {
        public string Title { get; set; }
        public string ImageName { get; set; }
        /// <summary>
        /// For ComboBox DisplayMember 
        /// </summary>
        /// <returns></returns>
        public override string ToString() => Title;
    }
}

电影运营

using System.Collections.Generic;
using System.Drawing;
using System.IO;
using Newtonsoft.Json;

namespace MoviesCodeSample
{
    /// <summary>
    /// Movie operations which requires Json.Net NuGet package
    /// or if using .NET Core 5 or higher use System.Text.Json
    /// </summary>
    public class MovieOperations
    {
        /*
         * Mocked up for demonstration, these two properties
         * can be stored under application settings or a json file
         * obtaining your settings rather than done via project properties.
         */
        public static string FolderName = "TODO";
        public static string FileName = Path.Combine(FolderName,"Movies.json");

        /// <summary>
        /// Mockup for demonstration purposes, you would create your own
        /// list, perhaps creating a utility that reads images, allows you
        /// to add descriptions for each movie save back to disk
        /// </summary>
        public static List<Movie> Movies => new List<Movie>()
        {
            new Movie() { Title = "Movie 1", ImageName = "checkmark.png" },
            new Movie() { Title = "Movie 2", ImageName = "Mail_16x.png" },
            new Movie() { Title = "Movie 3", ImageName = "upGreenArrow.png" }
        };

        public static void CreateInitialMoviesJsonFile()
        {
            File.WriteAllText(
                FileName, 
                JsonConvert.SerializeObject(Movies, Formatting.Indented));
        }

        /// <summary>
        /// Read movies from json file, in this case for
        /// demonstration a mocked up json file is created if not exists
        /// which in this case it does not.
        /// </summary>
        /// <returns>movies in json file</returns>
        public static List<Movie> GetMovies()
        {

            if (!File.Exists(FileName))
            {
                CreateInitialMoviesJsonFile();
            }

            return JsonConvert.DeserializeObject<List<Movie>>(
                File.ReadAllText(FileName));

        }

        /// <summary>
        /// Get current movie triggered from selection changed in the ComboBox
        /// on the calling form.
        /// </summary>
        /// <param name="name"></param>
        /// <returns></returns>
        public static Image GetMovieImage(string name) 
            => Image.FromFile(Path.Combine(FolderName, name));

    }
}

表格，一个PictureBox，一个ComboBox

using System;
using System.Windows.Forms;

namespace MoviesCodeSample
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
            Shown += OnShown;
        }

        private void OnShown(object sender, EventArgs e)
        {
            MoviesComboBox.DataSource = MovieOperations.GetMovies();
            MoviesComboBox.SelectedIndexChanged += MoviesComboBoxOnSelectedIndexChanged;
            ShowCurrentMovieImage();
        }

        private void MoviesComboBoxOnSelectedIndexChanged(object sender, EventArgs e)
        {
            ShowCurrentMovieImage();
        }

        private void ShowCurrentMovieImage()
        {
            MoviePictureBox.Image = MovieOperations.GetMovieImage(
                ((Movie)MoviesComboBox.SelectedItem).ImageName);
        }
    }
}

【讨论】：

【解决方案5】：

试试这个：

enter code here

private void button1_Click(object sender, EventArgs e)
    {
 if (comboBox1.SelectedIndex == 0)
 if (comboBox2.SelectedIndex == 0)
 if (comboBox3.SelectedIndex == 0)
    {
        pictureBox1.Image = Image.FromFile(@"C:\Users\Petter\Desktop\test\1.jpg");

}

enter code here

感谢您的指导 :) 我用过这个，效果很好 :)

====== SAURABH ======

【讨论】：