/// <summary>
/// Prepends a new content stream and returns it.
/// </summary>
public PdfContent PrependContent()
{
Debug.Assert(Owner != null);
SetModified();
PdfContent content = new PdfContent(Owner);
Owner._irefTable.Add(content);
Debug.Assert(content.Reference != null);
Elements.Insert(0, content.Reference);
return(content);
}
/// <summary>
/// Replaces the current content of the page with the specified bytes.
/// </summary>
PdfContent ReplaceContent(byte[] contentBytes)
{
Debug.Assert(Owner != null);
PdfContent content = new PdfContent(Owner);
content.CreateStream(contentBytes);
Owner._irefTable.Add(content);
Elements.Clear();
Elements.Add(content.Reference);
return(content);
}
void SetModified()
{
if (!_modified)
{
_modified = true;
int count = Elements.Count;
if (count == 1)
{
PdfContent content = (PdfContent)((PdfReference)Elements[0]).Value;
content.PreserveGraphicsState();
}
else if (count > 1)
{
// Surround content streams with q/Q operations
byte[] value;
int length;
PdfContent content = (PdfContent)((PdfReference)Elements[0]).Value;
if (content != null && content.Stream != null)
{
length = content.Stream.Length;
value = new byte[length + 2];
value[0] = (byte)'q';
value[1] = (byte)'\n';
Array.Copy(content.Stream.Value, 0, value, 2, length);
content.Stream.Value = value;
content.Elements.SetInteger("/Length", length + 2);
}
content = (PdfContent)((PdfReference)Elements[count - 1]).Value;
if (content != null && content.Stream != null)
{
length = content.Stream.Length;
value = new byte[length + 3];
Array.Copy(content.Stream.Value, 0, value, 0, length);
value[length] = (byte)' ';
value[length + 1] = (byte)'Q';
value[length + 2] = (byte)'\n';
content.Stream.Value = value;
content.Elements.SetInteger("/Length", length + 3);
}
}
}
}
/// <summary>
/// Creates a single content stream with the bytes from the array of the content streams.
/// This operation does not modify any of the content streams in this array.
/// </summary>
public PdfContent CreateSingleContent()
{
byte[] bytes = new byte[0];
byte[] bytes1;
byte[] bytes2;
foreach (PdfItem iref in Elements)
{
PdfDictionary cont = (PdfDictionary)((PdfReference)iref).Value;
bytes1 = bytes;
bytes2 = cont.Stream.UnfilteredValue;
bytes = new byte[bytes1.Length + bytes2.Length + 1];
bytes1.CopyTo(bytes, 0);
bytes[bytes1.Length] = (byte)'\n';
bytes2.CopyTo(bytes, bytes1.Length + 1);
}
PdfContent content = new PdfContent(Owner);
content.Stream = new PdfDictionary.PdfStream(bytes, content);
return(content);
}
