我是C#编程的新手,我正在尝试创建一个允许用户将信息和图片保存到Ms访问数据库的软件。我已经按照youtube上的教程设法存储了我需要的信息和图片,但我似乎无法检索图像并将其显示在图片框中。有谁可以帮助我?
我的代码是:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Data.OleDb;
using System.IO;
namespace ConnectionApp
{
public partial class ClinicaPrivada : Form
{
OleDbConnection DBConnection = new OleDbConnection();
OleDbDataAdapter DataAdapter;
DataTable LocalDatatable = new DataTable();
int rowPosition = 0;
int rowNumber = 0;
public ClinicaPrivada()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
ConnectToDatabase();
}
public void ConnectToDatabase()
{
DBConnection.ConnectionString = @"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=ClinicaPrivada.mdb";
DataAdapter = new OleDbDataAdapter("Select * From Pacientes", DBConnection);
DataAdapter.Fill(LocalDatatable);
if (LocalDatatable.Rows.Count != 0)
{
rowPosition = LocalDatatable.Rows.Count;
}
}
public void RefreshDBConnection()
{
if (DBConnection.State.Equals(ConnectionState.Open))
{
DBConnection.Close();
LocalDatatable.Clear();
ConnectToDatabase();
}
}
private void btnBrowse_Click(object sender, EventArgs e)
{
}
public byte[] ConvertAndStoreToDB(Image InputImage)
{
Bitmap BmpImage = new Bitmap(InputImage);
MemoryStream Mystream = new MemoryStream();
BmpImage.Save(Mystream, System.Drawing.Imaging.ImageFormat.Jpeg);
byte[] ImageAsBytes = Mystream.ToArray();
return ImageAsBytes;
}
public void StoreToDB(byte[] ImageAsBytes)
{
string NrDoPaciente;
NrDoPaciente = Convert.ToString(txtNrdoPaciente.Text);
string Empresa;
Empresa = Convert.ToString(txtEmpresa.Text);
string DataDaConsutla;
DataDaConsutla = Convert.ToString(txtDatadaConsulta.Text);
if (DBConnection.State.Equals(ConnectionState.Closed))
DBConnection.Open();
try
{
MessageBox.Show("Saving Image at index:" + rowPosition.ToString());
OleDbCommand insert = new OleDbCommand("Insert Into Pacientes (NrDoPaciente, Empresa, DatadaConsulta, Document) VALUES('" + NrDoPaciente +"','" + Empresa + "','" + DataDaConsutla + "','" + "Document" + "')" , DBConnection);
OleDbParameter InsertParameter = insert.Parameters.AddWithValue("Docu", SqlDbType.Binary);
int rowsAffected = insert.ExecuteNonQuery();
MessageBox.Show("Data Stored successfully in " + rowsAffected.ToString() + "Row");
rowPosition++;
}
catch (Exception ex)
{
MessageBox.Show(ex.Message.ToString());
MessageBox.Show(ex.StackTrace.ToString());
}
finally
{
RefreshDBConnection();
}
}
private Image ReadImageFromDB()
{
Image FetchedImg;
if (rowNumber >= 0)
{
byte[] FetchedImgBytes = (byte[])LocalDatatable.Rows[rowNumber]["Document"];
MemoryStream stream = new MemoryStream(FetchedImgBytes);
FetchedImg = Image.FromStream(stream);
return FetchedImg;
}
else
{
MessageBox.Show("There are no Images in the database yet. Please reconnect or add some images.");
return null;
}
}
private void btnBrowse_Click_1(object sender, EventArgs e)
{
if (openFileDialog1.ShowDialog() == DialogResult.OK)
{
pictureBox1.Image = Image.FromFile(openFileDialog1.FileName);
}
}
private void btnSave_Click_1(object sender, EventArgs e)
{
StoreToDB(ConvertAndStoreToDB(pictureBox1.Image));
}
private void btnDisplayAll_Click(object sender, EventArgs e)
{
RefreshDBConnection();
rowNumber = 0;
pictureBox2.Image = ReadImageFromDB();
btnNext.Enabled = true;
BtnPrevious.Enabled = true;
}
}
}
答案 0 :(得分:0)
创建数据表,如: 表: Id int,Image OLE Object
然后使用此代码插入
//Convert img into bytes
byte[] FileBytes = null;
string imgpath = "PatientsPhotos/" + lbl_patientID.Content.ToString() + ".jpg";
FileStream fs = new FileStream(imgpath,System.IO.FileMode.Open,System.IO.FileAccess.Read);
BinaryReader BR = new BinaryReader(fs);
long allbytes = new FileInfo(imgpath).Length;
FileBytes = BR.ReadBytes((Int32)allbytes);
patient.imagepath = FileBytes;
然后,插入' imagepath'进入Image place表
并从表中检索imagepath并转换为如下图像:
ImageSourceConverter imgConv = new ImageSourceConverter();
string path = ("PatientsPhotos/" + this.pt_id + ".jpg");
ImageSource imageSource = (ImageSource)imgConv.ConvertFromString(path);
imgVideo.Source = imageSource;
我认为这可能会对你有所帮助。谢谢
答案 1 :(得分:0)
您在内存中的图像可能超出范围。如果我是正确的,This question是直接相关的。
您必须制作图像的副本。否则,您的图像将链接到创建它的对象,当该对象超出范围时,您的图像数据将丢失。
我希望你从你想要做的事情中得到例外。
顺便说一句,我同意建议避免使用MS Access的评论者。有更好的免费选择。