第12章中文讲义(PPT).ppt

Chapter 12 Pointers and Dynamic Arrays Overview Pointers (12.1) Dynamic Arrays (12.2) Classes and Dynamic Arrays(12.3) 12.1 Pointers (夹) 夹ず甧琌跑计癘拘砰 癘拘砰ㄓ讽暗跑计嘿 安跑计惠璶 3 癘拘砰丁 (琌 byte 虫), 玥材 1 癘拘砰丁讽赣跑计嘿 讽跑计砆ノㄓ讽 call-by-reference 把计, ㄤ龟碞琌肚患ㄤ癘拘砰 Pointers Tell Where To Find A Variable 夹碞琌ノㄓ禗祘Α砞璸畍琘跑计癘拘砰 夹硓筁禗祘Α砞璸畍跑计纗柑┮弧夹  (損oint?to) 跑计 Declaring Pointers 夹跑计ゲ斗ΘΤ * Example: ㄒ double 跑计夹: double *p; ?? 夹ボ跑计 p 琌夹 Multiple Pointer Declarations 璶い夹–夹玡 ??Example:  int *p1, *p2, v1, v2;p1 and p2  type int 跑计v1 and v2 琌 type int 跑计 The address of Operator ??笲衡ノㄓ眔琘跑计ぇ癘拘砰赣挡狦倒赣跑计戈篈夹 Example: p1 = v1; 磅︽p1  v1 v1 砆嘿 損1 筁跑计 The Dereferencing Operator (矗烩埃癘拘砰) C++ ㄏノ ??笲衡矪瞶夹暗猭 損 筁跑计? C++ いノ *p ボ ??硂贺猵碞琌 矗烩 (dereferencing) 笲衡 p 硂贺猵碞琌砆矗烩 (dereferenced) 硂磅︽v1 の *p1跑计 A Pointer Example v1 = 0;p1 = v1;*p1 = 42;cout v1 endl;cout *p1 endl;块: 42 42 Pointer Assignment ﹚笲衡 ( = ) ノ夹 Example: 狦 p1  v1 玥 p2 = p1;  穦ㄏ *p2, *p1, の v1 常琌跑计ぃ嘿 Display 12.1 Caution! Pointer Assignments ㄏノ夹跑计ㄓ秈︽﹚ (assignment) 璶疭猔種ぃ p1= p3; // э跑 p1 ぇ癘拘砰 *p1 = *p3; // э跑 p1 ぇ癘拘砰柑 The new Operator ㄏノ夹, ㄏ⊿Τ跑计嘿э跑赣夹ぇ癘拘砰柑 ㄒ穝糤俱计 (int) ぇ礚跑计夹: p1 = new int; 硂跑计ノ *p1 ㄓ矪瞶 (ㄤ) *p1 ノヴ integer 跑计瞷よ cin *p1; *p1 = *p1 + 7; ㄏノ new 笲衡玻ネ跑计暗 笆篈跑计 (dynamic variables) 笆篈跑计 祘Α磅︽穦砆穝糤ㄤ癘拘砰丁 ┪ 癳倒穨╰参 Display 12.2 Τ pointers and dynamic variables 絛ㄒ Display 12.2 祘Α絏秆弧 Display 12.2 Display 12.3 Dynamic Variables new and Class Types new 笲衡ノ摸 (class) 戈篈穦㊣篶 (constructor) 皌竚癘拘砰倒赣ン 狦 MyType 琌