//.NET5
//ASP.NET Core 5上传文件
public async Task<ActionResult> UploadImg(IFormFile file)
{
//检查文件真实格式
System.IO.MemoryStream ms = new System.IO.MemoryStream();
await file.CopyToAsync(ms);
byte[] bytes = new byte[160];
ms.Position = 0;
await ms.ReadAsync(bytes, 0, bytes.Length);
bool pass = FileTypeCheck.IsValidFileExtension(file.FileName, bytes);
if (!pass)
{
return Json(new Result("文件格式不正确,允许的上传格式为" + allow_img_type));
}
object imgInfo = new
{
//图片保存文件名
fileName = objectName,
//存储桶
bucket = bucketName
};
return Json(imgInfo);
}
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace WebNetCore5_Img_Storage.Model.Tool
{
///
/// 文件真实格式检查
///
public class FileTypeCheck
{
private readonly static Dictionary<string, List<byte[]>> fileSignature = new Dictionary<string, List<byte[]>>
{
{ ".DOC", new List<byte[]> { new byte[] { 0xD0, 0xCF, 0x11, 0xE0, 0xA1, 0xB1, 0x1A, 0xE1 } } },
{ ".DOCX", new List<byte[]> { new byte[] { 0x50, 0x4B, 0x03, 0x04 } } },
{ ".PDF", new List<byte[]> { new byte[] { 0x25, 0x50, 0x44, 0x46 } } },
{ ".ZIP", new List<byte[]>
{
new byte[] { 0x50, 0x4B, 0x03, 0x04 },
new byte[] { 0x50, 0x4B, 0x4C, 0x49, 0x54, 0x55 },
new byte[] { 0x50, 0x4B, 0x53, 0x70, 0x58 },
new byte[] { 0x50, 0x4B, 0x05, 0x06 },
new byte[] { 0x50, 0x4B, 0x07, 0x08 },
new byte[] { 0x57, 0x69, 0x6E, 0x5A, 0x69, 0x70 }
}
},
//图片格式
{ ".PNG", new List<byte[]> { new byte[] { 0x89, 0x50, 0x4E, 0x47, 0x0D, 0x0A, 0x1A, 0x0A } } },
{ ".JPG", new List<byte[]>
{
new byte[] { 0xFF, 0xD8, 0xFF, 0xE0 },
new byte[] { 0xFF, 0xD8, 0xFF, 0xE1 },
new byte[] { 0xFF, 0xD8, 0xFF, 0xE8 }
}
},
{ ".JPEG", new List<byte[]>
{
new byte[] { 0xFF, 0xD8, 0xFF, 0xE0 },
new byte[] { 0xFF, 0xD8, 0xFF, 0xE2 },
new byte[] { 0xFF, 0xD8, 0xFF, 0xE3 }
}
},
{ ".GIF", new List<byte[]> { new byte[] { 0x47, 0x49, 0x46, 0x38 } } },
{ ".BMP", new List<byte[]> { new byte[] { 0x42, 0x4D } } },
{ ".JFIF", new List<byte[]> { new byte[] { 0xFF, 0xD8, 0xFF, 0xE0, 0x00, 0x10, 0x4A, 0x46, 0x49, 0x46 } } },
//视频格式
//高清,高占用空间
{ ".MP4", new List<byte[]> {
new byte[] { 0x00,0x00,0x00,0x18,0x66,0x74,0x79,0x70,0x6D,0x70,0x34,0x32 },
new byte[] { 0x00,0x00,0x00,0x1C,0x66,0x74,0x79,0x70,0x6D,0x70,0x34,0x32 },
new byte[] { 0x00,0x00,0x00,0x20,0x66,0x74,0x79,0x70,0x69,0x73,0x6F, 0x6D },
}
},
//高清,中度占用空间
{ ".MKV", new List<byte[]> {
new byte[] { 0x1A, 0x45, 0xDF, 0xA3, 0xA3, 0x42, 0x86, 0x81, 0x01, 0x42, 0xF7 }
}
},
//高清,中度占用空间
{ ".MOV", new List<byte[]> {
new byte[] { 0x00, 0x00, 0x00, 0x14, 0x66, 0x74, 0x79, 0x70, 0x71, 0x74 }
}
},
//高清,低占用空间
{ ".M4V", new List<byte[]> {
new byte[] { 0x00, 0x00, 0x00, 0x20, 0x66, 0x74, 0x79, 0x70, 0x4D, 0x34, 0x56 }
}
},
//高清,低占用空间
{ ".WEBM", new List<byte[]> {
new byte[] { 0x1A, 0x45, 0xDF, 0xA3, 0x9F, 0x42, 0x86, 0x81, 0x01, 0x42, 0xF7, 0x81, 0x01, 0x42, 0xF2 }
}
},
//低质量
{ ".WMV", new List<byte[]> {
new byte[] { 0x30,0x26,0xB2,0x75,0x8E,0x66,0xCF,0x11}
}
},
//低质量
{ ".AVI", new List<byte[]> {
new byte[] { 0x52, 0x49, 0x46, 0x46, 0x84, 0x4A, 0x1E, 0x00, 0x41, 0x56, 0x49 }
}
},
//低质量
{ ".FLV", new List<byte[]> {
new byte[] { 0x46, 0x4C, 0x56 }
}
},
//电子表格
{ ".XLS", new List<byte[]>
{
new byte[] { 0xD0, 0xCF, 0x11, 0xE0, 0xA1, 0xB1, 0x1A, 0xE1 },
new byte[] { 0x09, 0x08, 0x10, 0x00, 0x00, 0x06, 0x05, 0x00 },
new byte[] { 0xFD, 0xFF, 0xFF, 0xFF }
}
},
{ ".XLSX", new List<byte[]> { new byte[] { 0x50, 0x4B, 0x03, 0x04 } } },
};
///
/// 文件真实格式检查
///
/// 文件名,包含后缀
/// 文件头字节数组,请传200个以内
/// 允许的例外字节数组
///
public static bool IsValidFileExtension(string fileName, byte[] fileData, byte[] allowedChars = null)
{
if (string.IsNullOrEmpty(fileName) || fileData == null || fileData.Length == 0)
{
return false;
}
bool flag = false;
string ext = System.IO.Path.GetExtension(fileName);
if (string.IsNullOrEmpty(ext))
{
return false;
}
ext = ext.ToUpperInvariant();
//if (ext.Equals(".TXT") || ext.Equals(".CSV") || ext.Equals(".PRN"))
//{
// foreach (byte b in fileData)
// {
// if (b > 0x7F)
// {
// if (allowedChars != null)
// {
// if (!allowedChars.Contains(b))
// {
// return false;
// }
// }
// else
// {
// return false;
// }
// }
// }
// return true;
//}
if (!fileSignature.ContainsKey(ext))
{
return true;
}
List<byte[]> sig = fileSignature[ext];
foreach (byte[] b in sig)
{
var curFileSig = new byte[b.Length];
Array.Copy(fileData, curFileSig, b.Length);
if (curFileSig.SequenceEqual(b))
{
//验证格式通过
flag = true;
break;
}
}
return flag;
}
}
}