using Spire.Pdf 合并文件夹下.pdf 文件

using Spire.Pdf 

private void mergePDF()
{
List<string> filesList = new List<string>();
DirectoryInfo test = new DirectoryInfo(@"D:\LD\TR_lab\bin\Debug\report");
FileInfo[] Files = test.GetFiles("*.pdf");
foreach (var item in Files)
{
filesList.Add(@"D:\LD\TR_lab\bin\Debug\report\"+item.Name);
}

string outputFile = @"D:\LD\TR_lab\bin\Debug\report\"+DateTime.Now.ToString("yyyyMMddhhmmss") +".pdf";
String[] fileArry = filesList.ToArray();
PdfDocumentBase doc = PdfDocument.MergeFiles(fileArry);//合并文件
doc.Save(outputFile, FileFormat.PDF);//保存合并文件
System.Diagnostics.Process.Start(outputFile);//打开文件
}