/// <summary> /// 取小写文件名后缀 /// </summary> /// <param name="name">文件名</param> /// <returns>返回小写后缀，不带“.”</returns> public static string GetFileExt(string name) { return name.Split(".").Last().ToLower(); } /// <summary> /// 是否为图片文件 /// </summary> /// <param name="fileExt">文件扩展名，不含“.”</param> public static bool IsImage(string fileExt) { ArrayList al = new ArrayList { "bmp", "jpeg", "jpg", "gif", "png", "ico" }; return al.Contains(fileExt); } /// <summary> /// 检查是否允许文件 /// </summary> /// <param name="fileExt">文件后缀</param> /// <param name="allowExt">允许文件数组</param> public static bool CheckFileExt(string fileExt, string[] allowExt) { return allowExt.Any(t => t == fileExt); } /// <summary> /// 制作缩略图 /// </summary> /// <param name="original">图片对象</param> /// <param name="newFileName">新图路径</param> /// <param name="maxWidth">最大宽度</param> /// <param name="maxHeight">最大高度</param> public static void ThumbImg(Image original, string newFileName, int maxWidth, int maxHeight) { Size newSize = ResizeImage(original.Width, original.Height, maxWidth, maxHeight); using (Image displayImage = new Bitmap(original, newSize)) { try { displayImage.Save(newFileName, original.RawFormat); } finally { original.Dispose(); } } } /// <summary> /// 制作缩略图 /// </summary> /// <param name="fileName">文件名</param> /// <param name="newFileName">新图路径</param> /// <param name="maxWidth">最大宽度</param> /// <param name="maxHeight">最大高度</param> public static void ThumbImg(string fileName, string newFileName, int maxWidth, int maxHeight) { byte[] imageBytes = File.ReadAllBytes(fileName); Image img = Image.FromStream(new MemoryStream(imageBytes)); ThumbImg(img, newFileName, maxWidth, maxHeight); } /// <summary> /// 计算新尺寸 /// </summary> /// <param name="width">原始宽度</param> /// <param name="height">原始高度</param> /// <param name="maxWidth">最大新宽度</param> /// <param name="maxHeight">最大新高度</param> /// <returns></returns> private static Size ResizeImage(int width, int height, int maxWidth, int maxHeight) { if (maxWidth <= 0) maxWidth = width; if (maxHeight <= 0) maxHeight = height; decimal MAX_WIDTH = maxWidth; decimal MAX_HEIGHT = maxHeight; decimal ASPECT_RATIO = MAX_WIDTH / MAX_HEIGHT; int newWidth, newHeight; decimal originalWidth = width; decimal originalHeight = height; if (originalWidth > MAX_WIDTH || originalHeight > MAX_HEIGHT) { decimal factor; if (originalWidth / originalHeight > ASPECT_RATIO) { factor = originalWidth / MAX_WIDTH; newWidth = Convert.ToInt32(originalWidth / factor); newHeight = Convert.ToInt32(originalHeight / factor); } else { factor = originalHeight / MAX_HEIGHT; newWidth = Convert.ToInt32(originalWidth / factor); newHeight = Convert.ToInt32(originalHeight / factor); } } else { newWidth = width; newHeight = height; } return new Size(newWidth, newHeight); } /// <summary> /// 得到图片格式 /// </summary> /// <param name="name">文件名称</param> /// <returns></returns> public static ImageFormat GetFormat(string name) { string ext = GetFileExt(name); switch (ext) { case "ico": return ImageFormat.Icon; case "bmp": return ImageFormat.Bmp; case "png": return ImageFormat.Png; case "gif": return ImageFormat.Gif; default: return ImageFormat.Jpeg; } }
报错
2019-05-09 10:27:01,330 线程ID:[80] 日志级别：ERROR 出错类：WebApp.HttpGlobalExceptionFilter property:[(null)] - 错误描述：System.TypeInitializationException: The type initializer for 'System.DrawingCore.GDIPlus' threw an exception. ---> System.DllNotFoundException: Unable to load shared library 'gdiplus' or one of its dependencies. In order to help diagnose loading problems, consider setting the LD_DEBUG environment variable: libgdiplus: cannot open shared object file: No such file or directory at System.DrawingCore.GDIPlus.GdiplusStartup(UInt64& token, GdiplusStartupInput& input, GdiplusStartupOutput& output) at System.DrawingCore.GDIPlus..cctor() --- End of inner exception stack trace --- at System.DrawingCore.GDIPlus.GdipGetGenericFontFamilySansSerif(IntPtr& fontFamily) at System.DrawingCore.FontFamily..ctor(GenericFontFamilies genericFamily) at System.DrawingCore.FontFamily.get_GenericSansSerif() at System.DrawingCore.Font.CreateFont(String familyName, Single emSize, FontStyle style, GraphicsUnit unit, Byte charSet, Boolean isVertical) at Common.VerifyCodeHelper.CreateByteByImgVerifyCode(String verifyCode, Int32 width, Int32 height) in F:\src\WebApp\Common\VerifyCodeHelper.cs:line 206 at WebApp.Controllers.VerifyCodeController.NumberVerifyCode() in F:\src\WebApp\Controllers\VerifyCodeController.cs:line 27 at lambda_method(Closure , Object , Object[] ) at Microsoft.Extensions.Internal.ObjectMethodExecutor.Execute(Object target, Object[] parameters) at Microsoft.AspNetCore.Mvc.Internal.ActionMethodExecutor.SyncActionResultExecutor.Execute(IActionResultTypeMapper mapper, ObjectMethodExecutor executor, Object controller, Object[] arguments) at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.InvokeActionMethodAsync() at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.InvokeNextActionFilterAsync() at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.Rethrow(ActionExecutedContext context) at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.Next(State& next, Scope& scope, Object& state, Boolean& isCompleted) at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.InvokeInnerFilterAsync() at Microsoft.AspNetCore.Mvc.Internal.ResourceInvoker.InvokeNextExceptionFilterAsync()
解决方法
Centos 7
yum install libgdiplus-devel
原文地址：https://www.cnblogs.com/chenyishi/p/12302058.html
版权声明：本文内容由互联网用户自发贡献，该文观点与技术仅代表作者本人。本站仅提供信息存储空间服务，不拥有所有权，不承担相关法律责任。如发现本站有涉嫌侵权/违法违规的内容， 请发送邮件至 dio@foxmail.com 举报，一经查实，本站将立刻删除。