检查文件扩展名是否为图像的好方法 [英] Good way to check if file extension is of an image or not

问题描述

我具有此文件类型过滤器:

I have this file types Filters:

    public const string Png = "PNG Portable Network Graphics (*.png)|" + "*.png";
    public const string Jpg = "JPEG File Interchange Format (*.jpg *.jpeg *jfif)|" + "*.jpg;*.jpeg;*.jfif";
    public const string Bmp = "BMP Windows Bitmap (*.bmp)|" + "*.bmp";
    public const string Tif = "TIF Tagged Imaged File Format (*.tif *.tiff)|" + "*.tif;*.tiff";
    public const string Gif = "GIF Graphics Interchange Format (*.gif)|" + "*.gif";
    public const string AllImages = "Image file|" + "*.png; *.jpg; *.jpeg; *.jfif; *.bmp;*.tif; *.tiff; *.gif";
    public const string AllFiles = "All files (*.*)" + "|*.*";

    static FilesFilters()
    {
        imagesTypes = new List<string>();
        imagesTypes.Add(Png);
        imagesTypes.Add(Jpg);
        imagesTypes.Add(Bmp);
        imagesTypes.Add(Tif);
        imagesTypes.Add(Gif);
   }

OBS:.NET中是否有任何默认过滤器或免费的库?

OBS: Is there any default filters in .NET or a free library for that?

我需要一个静态方法来检查字符串是否为图像.您将如何解决这个问题?

I need a static method that checks if a string is an image or not. How would you solve this?

    //ext == Path.GetExtension(yourpath)
    public static bool IsImageExtension(string ext)
    {
        return (ext == ".bmp" || .... etc etc...)
    }

使用Jeroen Vannevel EndsWith的解决方案.我认为可以.

Solution using Jeroen Vannevel EndsWith. I think it is ok.

    public static bool IsImageExtension(string ext)
    {
        return imagesTypes.Contains(ext);
    }

推荐答案

您可以使用.endsWith(ext).不过，这不是一种非常安全的方法:我可以将"bla.jpg"重命名为"bla.png"，并且仍然是jpg文件.

You could use .endsWith(ext). It's not a very secure method though: I could rename 'bla.jpg' to 'bla.png' and it would still be a jpg file.

public static bool HasImageExtension(this string source){
 return (source.EndsWith(".png") || source.EndsWith(".jpg"));
}

此提供了更安全的解决方案:

This provides a more secure solution:

string InputSource = "mypic.png";
System.Drawing.Image imgInput = System.Drawing.Image.FromFile(InputSource);
Graphics gInput = Graphics.fromimage(imgInput);
Imaging.ImageFormat thisFormat = imgInput.rawformat;

这篇关于检查文件扩展名是否为图像的好方法的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！