//---------------------------------------------------------------------------------------------------------------------------------------------------------------------
// return Object of FileValidationConstraints with Default File Max Size and Default Allowed MimeTypes & Extensions For Document File And ImgFile
//---------------------------------------------------------------------------------------------------------------------------------------------------------------------
public static FileValidationConstraints MixDocAndImgConstraints()
{
FileValidationConstraints Constraints = new FileValidationConstraints();
Constraints.FileMaximumBytes = DefaultMaxSize;
Constraints.AllowedMimeTypes = new List <string>();
// Add Accepted MimeTypes For Microsoft Office for example : application/msword , ...
Constraints.AllowedMimeTypes.AddRange(AllowedMimeTypes_MicrosoftOffice);
// Add Accepted MimeTypes In General without Microsoft Office mime types for example : "text/plain", "application/pdf",...
Constraints.AllowedMimeTypes.AddRange(AllowedMimeTypes_GeneralDocuments);
// Add Accepted MimeTypes For Images for example : "Image/png",...
Constraints.AllowedMimeTypes.AddRange(AllowedMimeTypes_Images);
Constraints.AllowedExtension = new List <string>();
// Add Accepted Extensions For Microsoft Office for example : doc,docx , ...
Constraints.AllowedExtension.AddRange(AllowedExtensions_MicrosoftOffice);
// Add Accepted Extensions In General without Microsoft Office Extensions for example : .pdf,.txt , ...
Constraints.AllowedExtension.AddRange(AllowedExtensions_GeneralDocuments);
// Add Accepted Extensions For Images for example : .png, ...
Constraints.AllowedExtension.AddRange(AllowedExtensions_Images);
return(Constraints);
}
//---------------------------------------------------------------------------------------------------------------------------------------------------------------------
//@param (int) FileMaximumBytes : Maximum Size For The File In Bytes
//@param (List<string>) AllowedMimeTypes : List of Allowed Mime types to Validate Uploaded File
//@param (List<string>) AllowedExtension : List of Allowed Extensions to Validate Uploaded File
//
//return Object of FileValidationConstraints with File Max Size and Allowed MimeTypes & Extensions For Document File
//---------------------------------------------------------------------------------------------------------------------------------------------------------------------
public static FileValidationConstraints CustomConstraints(int FileMaximumBytes, List <string> AllowedMimeTypes, List <string> AllowedExtension)
{
FileValidationConstraints Constraints =
new FileValidationConstraints {
FileMaximumBytes = FileMaximumBytes, AllowedMimeTypes = AllowedMimeTypes, AllowedExtension = AllowedExtension
};
return(Constraints);
}
//---------------------------------------------------------------------------------------------------------------------------------------------------------------------
// return Object of FileValidationConstraints with Default Image Max Size and Default Allowed MimeTypes & Extensions For Image
//---------------------------------------------------------------------------------------------------------------------------------------------------------------------
public static FileValidationConstraints ImgConstraints()
{
FileValidationConstraints Constraints = new FileValidationConstraints();
Constraints.FileMaximumBytes = DefaultMaxSize;
Constraints.AllowedMimeTypes = new List <string>();
Constraints.AllowedMimeTypes.AddRange(AllowedMimeTypes_Images);
Constraints.AllowedExtension = new List <string>();
Constraints.AllowedExtension.AddRange(AllowedExtensions_Images);
return(Constraints);
}
//---------------------------------------------------------------------------------------------------------------------------------------------------------------------
//@param (IFormFile) postedFile : the uploaded file
//@param (FileValidationConstraints) constraints : this object has main Constraints to Validate the File Like Maximum file size and allowed MimeTypes & Extentions
//---------------------------------------------------------------------------------------------------------------------------------------------------------------------
public static bool IsValidFile(IFormFile postedFile, FileValidationConstraints constraints)
{
try
{
// List of Allowed MimeTypes and Extensions
List <string> MimeTypes_Allowed = constraints.AllowedMimeTypes;
List <string> Extension_Allowed = constraints.AllowedExtension;
//-------------------------------------------
// Check the file mime types
//-------------------------------------------
string contentType = postedFile.ContentType.ToLower();
if (!MimeTypes_Allowed.Any(m => m == contentType))
{
return(false);
}
//-------------------------------------------
// Check the file extension
//-------------------------------------------
string extension = Path.GetExtension(postedFile.FileName).ToLower();
if (!Extension_Allowed.Any(e => e == extension))
{
return(false);
}
//------------------------------------------
//check whether the file size exceeding the limit or not
//------------------------------------------
if (postedFile.Length > constraints.FileMaximumBytes)
{
return(false);
}
//---------------------------------------------------------------------------------------------------------------------------------
// Check the Real Mime Type Of File (because maybe user hacked the file and change his name and extension)
//---------------------------------------------------------------------------------------------------------------------------------
//MimeTypes is Custom Class not in Asp.net Classes
var actualType = MimeTypes.getMimeFromFile(postedFile);
if (!MimeTypes_Allowed.Any(m => m == actualType))
{
// Do Final Validation : check if its MicrosoftOfficeDocument in zip format otherwise return false
bool isMSOffice = isMicrosoftOfficeDocument(actualType, contentType, extension);
if (!isMSOffice)
{
return(false);
}
}
return(true);
}
catch (Exception)
{
return(false);
}
}
