执行如下代码: #import<Foundation/Foundation.h>#import"MJPerson.h"intmain(intargc,constchar*argv[]){@autoreleasepool{MJPerson*p=[[MJPerson alloc]init];p.data=[NSMutableArray array];[p.data addObject:@"jack"];//报错[p.data addObject:@"rose"];[p release];}return0;} 发现会报错: -[__N...
从0x00-0x0a共11个字节,是BinarySignature,static const char BinarySignature[11] = "PGCOPY\n\377\r\n\0"; 其中\377是255的8进制形式 从0x0b-0x0e共4字节, 是Flags field,固定为0 从0x0f-0x12共4字节, 是header extension,0表示长度是0,后面无数据。如果有数据的话,根据长度值获取数据。 然后后面...
char* p = greeting;//non-const pointer, non-const dataconstchar* p = greeting;//non-const pointer, const datachar*constp = greeting;//const pointer, non-const dataconstchar*constp = greeting;//const pointer, const data 如果被指物是常量,关键词const写在类型或写在类型时候星号之前的意义都...
intmain(intargc,constchar*argv[]){@autoreleasepool{NSString*str1=[NSString stringWithFormat:@"季末"];NSString*str2=[str1 copy];NSMutableString*str3=[str1 mutableCopy];NSLog(@"%@ %p",str1,str1);NSLog(@"%@ %p",str2,str2);NSLog(@"%@ %p",str3,str3);}return0;}2019-06-0714:56:...
#include <string.h> char *strcpy(char *string1, const char *string2); Language Level ANSI Threadsafe Yes Description Thestrcpy()function copiesstring2, including the ending null character, to the location that is specified bystring1.
*/copy_data_source_cbdata_source_cb;/* function for reading data */CopyFormatOptionsopts;bool*convert_select_flags;/* per-column CSV/TEXT CS flags */Node*whereClause;/* WHERE condition (or NULL) *//* these are just for error messages, see CopyFromErrorCallback */constchar*cur_relname...
int main(int argc, const char * argv[]){ autoreleasepool { Fraction *f1 = [[Fraction alloc] init];Fraction *f2;[f1 setTo:2 over:5];f2 = [f1 copy];[f2 setTo:1 over:3];[f1 print];[f2 print];[f1 release];[f2 release];} return 0;} 由此可以实现对自定义类Fraction...
函数定义: int open( const char * pathname, int flags); int open( const char * pathname,int flags, mode_t mode); 参数说明: pathname :文件的名称,可以包含(绝对和相对)路径 flags:文件打开模...
// PtrToStringChars, from vcclr.h // get an interior gc pointer to the first character contained in a // System::String object // inline const System::Char * PtrToStringChars(const System::String *s) { const System::Byte *bp = reinterpret_cast<const System::Byte *>(s); if( bp ...
I do need to write my own Copy Constructor and Assignment Operator though, because unique_ptr does not define these operations... but it doesn't matter here ;) And therefore, sharptooth's class revisited: class Class { public: Class(char const* str): mData(str) {} private: std::...