dotnet获取PDF文件的页数

#region 获取PDF文件的页数 private int BytesLastIndexOf(Byte[] buffer, int length, string Search)
{
if (buffer == null)
return -;
if (buffer.Length <= )
return -;
byte[] SearchBytes = Encoding.Default.GetBytes(Search.ToUpper());
for (int i = length - SearchBytes.Length; i >= ; i--)
{
bool bFound = true;
for (int j = ; j < SearchBytes.Length; j++)
{
if (ByteUpper(buffer[i + j]) != SearchBytes[j])
{
bFound = false;
break;
}
}
if (bFound)
return i;
}
return -;
} private byte ByteUpper(byte byteValue)
{
char charValue = Convert.ToChar(byteValue);
if (charValue < 'a' || charValue > 'z')
return byteValue;
else
return Convert.ToByte(byteValue - );
} /// <summary>
/// 获取pdf文件的页数
/// </summary>
public int GetPDFPageCount(string path) //获取pdf文件的页数
{
path = HttpContext.Current.Server.MapPath(path);
byte[] buffer = File.ReadAllBytes(path);
int length = buffer.Length;
if (buffer == null)
return -;
if (buffer.Length <= )
return -;
try
{
//Sample
// 29 0 obj
// <</Count 9
// Type /Pages
int i = ;
int nPos = BytesLastIndexOf(buffer, length, "/Type/Pages");
if (nPos == -)
return -;
string pageCount = null;
for (i = nPos; i < length - ; i++)
{
if (buffer[i] == '/' && buffer[i + ] == 'C' && buffer[i + ] == 'o' && buffer[i + ] == 'u' && buffer[i + ] == 'n' && buffer[i + ] == 't')
{
int j = i + ;
while (buffer[j] != '/' && buffer[j] != '>')
j++;
pageCount = Encoding.Default.GetString(buffer, i, j - i);
break;
}
}
if (pageCount == null)
return -;
int n = pageCount.IndexOf("Count");
if (n > )
{
pageCount = pageCount.Substring(n + ).Trim();
for (i = pageCount.Length - ; i >= ; i--)
{
if (pageCount[i] >= '' && pageCount[i] <= '')
{
return int.Parse(pageCount.Substring(, i + ));
}
}
}
return -;
}
catch (Exception ex)
{
return -;
}
} #endregion