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/// <summary>
/// 图片，字节流，路径文件的转换
/// </summary>
class BitmapImageHelper
{
//待测试
public Image GetImageHttp(string url, int width)
{
Image image = null;
int BytesToRead = 100;
if (!string.IsNullOrEmpty(url))
{
WebRequest request = WebRequest.Create(new Uri(url, UriKind.Absolute));
request.Timeout = -1;
WebResponse response = request.GetResponse();
if (response != null)
{
Stream responseStream = response.GetResponseStream();
BinaryReader reader = new BinaryReader(responseStream);
MemoryStream memoryStream = new MemoryStream();
byte[] bytebuffer = new byte[BytesToRead];
int bytesRead = reader.Read(bytebuffer, 0, BytesToRead);
while (bytesRead > 0)
{
memoryStream.Write(bytebuffer, 0, bytesRead);
bytesRead = reader.Read(bytebuffer, 0, BytesToRead);
}
memoryStream.Close();
reader.Close();
responseStream.Close();
response.Close();
}
}
return image;
}
/// <summary>
/// 获取远程地址的图片(经测试显示参数无效,可以保存到指定文件夹下)，需进一步测试
/// </summary>
/// <param name="url">远程地址</param>
/// <returns></returns>
public static Image GetImageHttp(string url)
{
try
{
LogerHelper.CreateLogTxt($"GetImageHttp 照片地址{url}");
WebRequest webreq = WebRequest.Create(new Uri(url, UriKind.Absolute));
WebResponse webres = webreq.GetResponse();
// 以字符流的方式读取HTTP响应，使用Using// 释放资源
using (Stream stream = webres.GetResponseStream())
{
//string path = Directory.GetCurrentDirectory() + "\\Photos";
string path = @"D:\Photos";//photos为保存到的照片名称
Image.FromStream(stream).Save(path);
return Image.FromStream(stream);
}
}
catch (Exception ex)
{
LogerHelper.CreateLogTxt($"获取照片错误{ex.Message}");
}
return null;
}
/// <summary>
/// 获取远程地址的图片
/// </summary>
/// <param name="url">远程地址</param>
/// <returns></returns>
public static Image GetImagePath(string url)
{
return UrlToImage(url);
}
/// <summary>
/// 根据远程地址获取图片流
/// </summary>
/// <param name="url"></param>
/// <returns></returns>
public static byte[] GetImageBytePath(string url)
{
WebClient mywebclient = new WebClient();
byte[] Bytes = mywebclient.DownloadData(url);
return Bytes;
}
#region 把在线图片转为base64
/// <summary>
///
/// </summary>
/// <param name="fileFullName">远程成在线图片地址</param>
/// <returns></returns>
public static string ImageToBase64(string fileFullName)
{
try
{
LogerHelper.CreateLogTxt($"ImageToBase64 照片地址{fileFullName}");
Image img = UrlToImage(fileFullName);
Bitmap bmp = new Bitmap(img);
MemoryStream ms = new MemoryStream();
var suffix = fileFullName.Substring(fileFullName.LastIndexOf('.') + 1,
fileFullName.Length - fileFullName.LastIndexOf('.') - 1).ToLower();
var suffixName = suffix == "png" || suffix == "jpng"
? ImageFormat.Png
: suffix == "jpg" || suffix == "jpeg"
? ImageFormat.Jpeg
: suffix == "bmp"
? ImageFormat.Bmp
: suffix == "gif"
? ImageFormat.Gif
: ImageFormat.Jpeg;
bmp.Save(ms, suffixName);
byte[] arr = new byte[ms.Length]; ms.Position = 0;
ms.Read(arr, 0, (int)ms.Length); ms.Close();
string base64Str = Convert.ToBase64String(arr);
return PrefectBase64(base64Str);
}
catch (Exception ex)
{
return null;
}
}
/// <summary>
/// 通过远程地址获取图片， 会出现（GDI+中发生一般性错误的解决方法：释放图片资源）错误，未解决
/// </summary>
/// <param name="url">远程地址串</param>
/// <returns></returns>
private static Image UrlToImage(string url)
{
WebClient mywebclient = new WebClient();
byte[] Bytes = mywebclient.DownloadData(url);
MemoryStream ms = new MemoryStream(Bytes);
Image outputImg = Image.FromStream(ms);
return outputImg;
//using (MemoryStream ms = new MemoryStream(Bytes))
//{
// Image outputImg = Image.FromStream(ms);
// //GetBytes(outputImg);
// return outputImg;
//}
}
private static string PrefectBase64(string Base64Str)
{
string dummyData = Base64Str.Replace("%", "").Replace(",", "").Replace(" ", "+");
if (dummyData.Length % 4 > 0)
{
dummyData = dummyData.PadRight(dummyData.Length + 4 - dummyData.Length % 4, '=');
}
return dummyData;
}
#region Image To base64
/// <summary>
/// Image 转成 base64
/// </summary>
/// <param name="fileFullName"></param>
public static string ImageToBase64E(Image img)
{
try
{
Bitmap bmp = new Bitmap(img);
MemoryStream ms = new MemoryStream();
bmp.Save(ms, ImageFormat.Jpeg);
byte[] arr = new byte[ms.Length];
ms.Position = 0;
ms.Read(arr, 0, (int)ms.Length);
ms.Close();
return Convert.ToBase64String(arr);
}
catch (Exception ex)
{
return null;
}
}
public static string ImageToBase64E(string url)
{
return ImageToBase64E(UrlToImage(url));
}
#endregion
#endregion
/// <summary>
/// base64转图片
/// </summary>
/// <param name="base64"></param>
public static Image Base64ToImage(string base64)
{
try
{
base64 = base64.Replace("data:image/png;base64,", "").Replace("data:image/jgp;base64,", "").Replace("data:image/jpg;base64,", "").Replace("data:image/jpeg;base64,", "").Replace("data:image/jpng;base64,", "").Replace("data:image/jpng;base64;", "");//将base64头部信息替换
byte[] bytes = Convert.FromBase64String(base64);
MemoryStream memStream = new MemoryStream(bytes);
Image mImage = Image.FromStream(memStream);
return mImage;
//Bitmap bp = new Bitmap(mImage);
//string path = @"D:\uploads";
//if (!Directory.Exists(path))
//{
// Directory.CreateDirectory(path);
//}
//DateTime now = DateTime.Now;
//string fileName = "images";
//string filePath = path + "\\" + fileName;
//bp.Save(filePath, System.Drawing.Imaging.ImageFormat.Jpeg);//注意保存路径
}
catch (Exception ex)
{
LogerHelper.CreateLogTxt($"base64转图片失败，错误详情: {ex.Message}");
throw;
}
}
/// <summary>
/// 图片转字节数组
/// </summary>
/// <param name="Picture"></param>
/// <returns></returns>
public static byte[] ImageToByte(Image Pic)
{
MemoryStream ms = new MemoryStream();
if (Pic == null)
return new byte[ms.Length];
Pic.Save(ms, ImageFormat.Jpeg);
byte[] BPicture = new byte[ms.Length];
BPicture = ms.GetBuffer();
return BPicture;
}
/// <summary>
/// 字节流转图片
/// </summary>
/// <param name="btImage"></param>
/// <returns></returns>
public static Image ByteToImage(byte[] byImage)
{
if (byImage.Length == 0)
return null;
MemoryStream ms = new MemoryStream(byImage);
Image image = Image.FromStream(ms);
return image;
}
/// <summary>
/// 根据图片路径返回图片的字节流byte[]
/// </summary>
/// <param name="imagePath">图片路径</param>
/// <returns>返回的字节流</returns>
public static byte[] getImageByte(string imagePath)
{
FileStream files = new FileStream(imagePath, FileMode.Open);
byte[] imgByte = new byte[files.Length];
files.Read(imgByte, 0, imgByte.Length);
files.Close();
return imgByte;
}
/// <summary>
/// GDI+中发生一般性错误的解决方法：释放图片资源
/// </summary>
/// <param name="image"></param>
/// <returns></returns>
private static byte[] GetBytes(Image image)
{
try
{
if (image == null) return null;
using (Bitmap bitMap = new Bitmap(image))
{
using (MemoryStream stream = new MemoryStream())
{
bitMap.Save(stream,ImageFormat.Jpeg);
return stream.GetBuffer();
}
}
}
finally
{
if (image != null)
{
image.Dispose();
image = null;
}
}
}
}
LogerHelper类见链接：https://mp.csdn.net/mp_blog/creation/editor/89875205
