C#基础笔记

nt was created with Spire.PDF for .NET.\rStringBuilderL(%BN!O+ZopN!Oqr`s%>t;l\ruCp%`?vwxyzMjmncd{%>|}~uC,\rf€[(‚hiƒu{j„…P`†‡+ˆ‰ab1 6 yz6\ruCŠ‹uCMŒj|ƒuuC>op62 Žƒu\rStringbulder:efvN!O6P:\rstring6*** (’“`’”•M,’[(p–—++\r˜™ IndexOf LastlndexOf Contains(š›+ Starts With EndWith\rf œ (P:+ Concat Join\r Substring Split\ržŸ Pad Left PadRigth\rc¡ Trim TrimStar TrimEnd\rr` Insert (¢£+WRemove (¤¥+ Replace (¦§+\r¡*0?String.Format\r¨?©ª?Tollpper Tolower\r«˜c¬DcN!­IsNullOrEmpty\rstring str2=null M%P:\rstring str2 = " " %>P:\rN!ODN!6l®¯\rA>N!O`°±²]³p´µ.\r¶·¸¹\rpr i vate static i nt Sum (i nt n) ÉÊ˶·¸¹\rif (n <= 1)\r(\rreturn 1;\r}\rreturn (Sum (n-2) +Sum(n-1));\r)