在列表视图中绘制图像
本文关键字:绘制 图像 视图 列表 | 更新日期: 2023-09-27 18:07:00
我试图使这个目录应用程序显示其"标题"answers"类别"的图像,但我似乎无法显示图像,因为一个错误在
那一行images.Images.Add(row["id"].ToString(), new Bitmap(image_stream));
这是我的全部代码。我需要的解决方案,所以我可以打印图像与其相应的详细信息在一个列表视图。谢谢你。
namespace WindowsFormsApplication2
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
comboBox1.Items.Add("Books");
comboBox1.Items.Add("Games");
comboBox1.Items.Add("Music");
}
SqlConnection connection = new SqlConnection("Data Source=DESKTOP-4T5BLQ6''SQLEXPRESS;Initial Catalog=CatalogDB;Integrated Security=True");
SqlCommand command = new SqlCommand();
SqlDataAdapter dataAdapter = new SqlDataAdapter();
SqlDataReader dataReader;
DataTable dataTable = new DataTable();
MemoryStream stream1;
byte[] photo_array;
private void Form1_Load(object sender, EventArgs e)
{
}
private void button1_Click(object sender, EventArgs e)
{
connection.Open();
int i = 0;
MemoryStream stream = new MemoryStream();
command.CommandText = "insert into EntryTable(Title,Category,Image) values('" + textBox1.Text + "','" + comboBox1.Text + "','" + pictureBox1.Image + "')";
pictureBox1.Image.Save(stream, System.Drawing.Imaging.ImageFormat.Jpeg);
byte[] pic = stream.ToArray();
if (i > 0)
{
MessageBox.Show("Saved new item in index" + i);
}
connection.Close();
MessageBox.Show("Made New Entry");
showData();
clear();
}
void clear()
{
textBox1.Clear();
pictureBox1.Image = null;
comboBox1.SelectedIndex = -1;
}
private void button2_Click(object sender, EventArgs e)
{
OpenFileDialog ofd = new OpenFileDialog();
ofd.Filter = "Images only. |*.jpg; *jpeg; *.png; *.gif; *.bmp;";
DialogResult result = ofd.ShowDialog();
if (result == DialogResult.OK)
{
pictureBox1.Image = Image.FromFile(ofd.FileName);
}
}
private void showData()
{
connection.Open();
listView1.Clear();
ImageList images = new ImageList();
images.ColorDepth = ColorDepth.Depth32Bit;
listView1.LargeImageList = images;
listView1.LargeImageList.ImageSize = new System.Drawing.Size(100 , 100);
command.Connection = connection;
command.CommandText = "SELECT * FROM EntryTable";
dataAdapter.SelectCommand = command;
dataTable.Clear();
dataAdapter.Fill(dataTable);
foreach (DataRow row in dataTable.Rows)
{
var image_buffer = (byte[])(row["Image"]);
MemoryStream image_stream = new MemoryStream(image_buffer, true);
image_stream.Write(image_buffer, 0, image_buffer.Length);
images.Images.Add(row["id"].ToString(), new Bitmap(image_stream));
image_stream.Close();
ListViewItem listItem = new ListViewItem();
listItem.Text = row["Title"].ToString();
listItem.ImageKey = row["Image"].ToString();
listView1.Items.Add(listItem);
listView1.Items.Add(row["Category"].ToString());
listView1.Items.Add(row["Title"].ToString());
}
connection.Close();
}
}
}
Xoriel,
你需要更具体地说明你在SO上的要求。你原来的帖子只表明你有一个错误,这是阻碍你的应用程序开发(欢迎编码)。你甚至没有告诉我们你得到了什么错误。
现在你问如何实现一个try catch?你应该自己做一些调查。至于try catch,你可以从这里开始。
你的代码表明缺乏对windows winforms如何实例化及其事件顺序的理解。对我来说,这表明在这个问题解决后,您还会遇到更多的问题,所以我将在您的代码中添加一个try catch。它将把异常写入控制台。
foreach (DataRow row in dataTable.Rows)
{
var image_buffer = (byte[])(row["Image"]);
MemoryStream image_stream = new MemoryStream(image_buffer, true);
image_stream.Write(image_buffer, 0, image_buffer.Length);
try
{
images.Images.Add(row["id"].ToString(), new Bitmap(image_stream));
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
image_stream.Close();
ListViewItem listItem = new ListViewItem();
listItem.Text = row["Title"].ToString();
listItem.ImageKey = row["Image"].ToString();
listView1.Items.Add(listItem);
listView1.Items.Add(row["Category"].ToString());
listView1.Items.Add(row["Title"].ToString());
}
你真正的问题是你将图像存储到数据库的格式和你检索图像的方式。
问候,Marc