基本数据类型与字符串的转换

/*基本数据类型与字符串的相互转换 基本数据类型(int,float,double char)1> int类型转换成字符串2> float->NSString3> double->NSString4> char->NSString5> NSString->int6> NSString->float7>NSString->double8>将字符串中的字母转化成大写9>将字符串的字母转换成小写10>将首字母大写 */int main(int argc, const char * argv[]) {    @autoreleasepool {               int i = 5;        NSString * str = [[NSString alloc] initWithFormat:@"%d",i];        NSLog(@"%@",str);              float f = 9.8;        NSString * str1 = [[NSString alloc] initWithFormat:@"%.2f",f];        NSLog(@"%@",str1);                       double d = 4.5677;        NSString * str2 = [[NSString alloc] initWithFormat:@"%.6f",d];        NSLog(@"str2 %@",str2);               char c = 'a';        NSString * str3 = [[NSString alloc] initWithFormat:@"%c",c];        NSLog(@"%@",str3);                NSString * str4 = @"10";        int i1 = [str4 intValue];        NSLog(@"%d",i1);        NSString * str5 = @"1.5";        float f1 = [str5 floatValue];        NSLog(@"%.2f",f1);                NSString * str6 = @"7.98";        double d1 = [str6 doubleValue];        NSLog(@"%.5f",d1);                NSString * str7 = @"i386";        int i2 = [str7 intValue];        NSLog(@"%d",i2);                            NSString * str8 = @"baidu";        NSString * str9 = [str8 uppercaseString];        NSLog(@"%@",str9);                NSString * str10 = @"CHINA";        NSString * str11 = [str10 lowercaseString];        NSLog(@"%@",str11);                              NSString * str12 = [str10 capitalizedString];        NSLog(@"%@",str12);            }    return 0;}