//根据初始化方法创建字符串
NSString *str1 = [[NSString alloc] initWithString:@"name"];
NSLog(@"%@",str1);
NSString *str11 = @"name";
NSLog(@"%@",str11);
//根据构造方法创建字符串
NSString *str2 = [NSString stringWithString:@"name"];
NSLog(@"%@",str2);
//将C语言字符串转换成OC字符串
char *cStr = "hehe";
NSString *str3 = [[NSString alloc] initWithCString:cStr encoding:NSUTF8StringEncoding];
NSLog(@"%@",str3);
NSString *str4 = [NSString stringWithCString:cStr encoding:NSUTF8StringEncoding];
NSLog(@"%@",str4);
//根据指定格式创建字符串
NSString *str5 = [[NSString alloc] initWithFormat:@"%@+%d",@"duke",1001];
NSLog(@"%@",str5);
NSString *str6 = [NSString stringWithFormat:@"%@+%d",@"duke",1001];
NSLog(@"%@",str6);
//根据指定路径的文件的内容创建字符串
NSString *str7 = [[NSString alloc] initWithContentsOfFile:@"/Users/chentianyu/Desktop/abc.txt" encoding:NSUTF8StringEncoding error:nil];
NSLog(@"%@",str7);
NSString *str8 = [NSString stringWithContentsOfFile:@"/Users/chentianyu/Desktop/abc.txt" encoding:NSUTF8StringEncoding error:nil];
NSLog(@"%@",str8);
//求字符串的长度
NSInteger length = [str8 length];
NSLog(@"%ld",(long)length);
//判断一个字符串是否拥有前缀字符串和后缀字符串
BOOL result1 = [str8 hasPrefix:@"a"];
NSLog(@"%@",result1?@"YES":@"NO");
BOOL result2 = [str8 hasSuffix:@"c"];
NSLog(@"%@",result2?@"YES":@"NO");
//字符串比较和比较结果
NSComparisonResult result4 = [str8 compare:str7];
NSLog(@"%ld",result4);
//获取子字符串
//从指定下标(包含指定下标)到字符串结束的子字符串
NSString *subStr1 = [str8 substringFromIndex:2];
NSLog(@"%@",subStr1);
//从字符串开始到指定下标的字符(不包含指定下标的字符)的子字符串。
NSString *subStr2 = [str8 substringToIndex:2];
NSLog(@"%@",subStr2);
NSRange range = NSMakeRange(1, 3);
NSString *subStr3 = [str8 substringWithRange:range];
NSLog(@"%@",subStr3);
//字符串拼接
NSString *newStr1 = [str8 stringByAppendingString:@"dddd"];
NSLog(@"%@",newStr1);
//根据指定的格式串以及参数去拼接产生新的字符串
NSString *newStr2 = [str8 stringByAppendingFormat:@"%d",1001];
NSLog(@"%@",newStr2);
//路径拼接
NSString *newStr3 = [str8 stringByAppendingPathComponent:@"xx.avi"];
NSLog(@"%@",newStr3);
//字符串的替换
NSString *newString4 = [str8 stringByReplacingOccurrencesOfString:@"a" withString:@"误伤"];
NSLog(@"%@",newString4);
//字符与数值类型数据的转换
NSString *numString1 = @"1";
NSInteger integerValue = [numString1 integerValue];
NSLog(@"%ld",integerValue);
NSString *caseString = @"i love you ";
NSLog(@"%@",[caseString capitalizedString]);
//可变字符串的操作
//使用init初始化可变字符串
NSMutableString *mutableString = [[NSMutableString alloc] init];
NSLog(@"%@",mutableString);
//使用string初始化可变字符串
NSMutableString *mutableString2 = [NSMutableString string];
//可变字符串的拼接
[mutableString appendString:@"danshi"];
NSLog(@"%@",mutableString);
//删除字符串
[mutableString deleteCharactersInRange:NSMakeRange(1, 3)];
NSLog(@"%@",mutableString);
//插入字符串
[mutableString insertString:@"henhao" atIndex:1];
NSLog(@"%@",mutableString);
//使用初始化定义NSArray
NSArray *array1 = [[NSArray alloc] initWithObjects:@"1",@"2",@"哈哈", nil];
NSLog(@"%@",[array1 description]);
//使用构造方法定义NSArray
NSArray *array2 = [NSArray arrayWithObjects:@"2",@"2",@"2", nil];
NSLog(@"%@",array2);
//数组的语法糖形式
NSArray *array3 = @[@"1",@2,@"3"];
NSLog(@"%@",array3);
//获取数组元素个数
NSInteger count = [array3 count];
NSLog(@"%ld",count);
//通过下标获取对应的对象
for (int i = 0; i < [array3 count]; i++) {
NSLog(@"%@",array3[i]);
}
//通过对象去查找它在数组中的下标
NSLog(@"%ld",[array3 indexOfObject:@2]) ;
//
NSString *textString = [[NSString alloc] initWithContentsOfFile:@"/Users/chentianyu/Desktop/abc.txt" encoding:NSUTF8StringEncoding error:nil];
NSLog(@"%@",textString);
NSArray *array4 =[textString componentsSeparatedByString:@"\n"];
NSLog(@"%@",array4);
//可变数组的使用
