[C #] Creating and calling dll files

1: Write MySwap. cs file: [csharp] using System; using System. collections. generic; using System. linq; using System. text; namespace Mydll // namespace {public class MySwap {public static void Swap (long I, long j) {I = I + j; j = I-j; I = I-j; Console. writeLine ("FirstNum =" + I + ", SecondNum =" + j) ;}}2: Add environment variables to my computer: my computer-properties-advanced-Environment Variable-system variable-Path: add C: \ WINDOWS \ Microsoft. NET \ Framework \ v4.0.30319; 3: copy the cs file to the C: \ Documents ents and Settings \ zhangjk directory (for more information about this directory, see Step 4. Ensure consistency). 4: run csc/target: library MySwap in cmd. cs 5: Generate MySwap under the C: \ Documents and Settings \ zhangjk directory. dll file add application to project reference :( if the namespace is inconsistent, You need to introduce namespace)