C#创建一个生成DEI文件的类,把实际类转成EDI文件，使用FFTIN布局规范定义了一个平面文件运输指令，需要的数据长度分别为2,1,3,1,14,35,3,35,100,255,50,250,50,45,45,12,70,70,3,1,14,100

以下是一个用C#创建生成DEI文件的类的示例：

public class EDIFileGenerator
{
    public static byte[] GenerateEDIFile(MyDataObject data)
    {
        // Create a new MemoryStream to hold the EDI file contents
        MemoryStream stream = new MemoryStream();
        
        // Create a new StreamWriter to write to the MemoryStream
        StreamWriter writer = new StreamWriter(stream);
        
        // Write the data to the file according to the FFTIN layout specification
        writer.Write(data.Field1.PadLeft(2));
        writer.Write(data.Field2.PadLeft(1));
        writer.Write(data.Field3.PadLeft(3));
        writer.Write(data.Field4.PadLeft(1));
        writer.Write(data.Field5.PadRight(14));
        writer.Write(data.Field6.PadRight(35));
        writer.Write(data.Field7.PadLeft(3));
        writer.Write(data.Field8.PadRight(35));
        writer.Write(data.Field9.PadRight(100));
        writer.Write(data.Field10.PadRight(255));
        writer.Write(data.Field11.PadRight(50));
        writer.Write(data.Field12.PadRight(250));
        writer.Write(data.Field13.PadRight(50));
        writer.Write(data.Field14.PadRight(45));
        writer.Write(data.Field15.PadRight(45));
        writer.Write(data.Field16.PadLeft(12));
        writer.Write(data.Field17.PadRight(70));
        writer.Write(data.Field18.PadRight(70));
        writer.Write(data.Field19.PadLeft(3));
        writer.Write(data.Field20.PadLeft(1));
        writer.Write(data.Field21.PadRight(14));
        writer.Write(data.Field22.PadRight(100));
        
        // Flush the StreamWriter to write the data to the MemoryStream
        writer.Flush();
        
        // Get the byte array representation of the MemoryStream
        byte[] ediFile = stream.ToArray();
        
        // Close the StreamWriter and MemoryStream
        writer.Close();
        stream.Close();
        
        // Return the byte array containing the EDI file contents
        return ediFile;
    }
}

这个示例假设你有一个名为MyDataObject的类，它包含与FFTIN布局规范定义的字段对应的属性。你可以将实际数据对象传递到GenerateEDIFile方法中，并且它将返回一个包含EDI文件内容的字节数组。要使用这个类，你需要根据你的数据对象的属性来实现它。