为字符串数组的每个元素添加前缀

Question

是否有快速方法为字符串数组中的每个元素添加字符串前缀？

Answer 1

定义NSMutableString

的类别

@implementation NSMutableString (AppendPrefix)

- (void)appendPrefix:(NSString *)prefix {
    [self insertString:prefix atIndex:0];
}

@end

然后做：

[array makeObjectsPerformSelector:@selector(appendPrefix:) withObject:@"some_prefix"];

array这里是NSArray的{​​{1}}

Answer 2

它有点长，但这应该有效：

- (NSArray *) prependArrayOfStrings:(NSArray*)originalArray prefix:(NSString*)prefix
{
  NSMutableArray *newArray = [[[NSMutableArray alloc] init] autorelease];
  for( NSString *currString in originalArray )
  {
    NSString *newString = [NSString stringwithFormat:@"%@%@", prefix, currString];
    [newArray addObject:newString];
  }

  return newArray;
}

---

// Somewhere else.
NSArray *originalArray = @[/*...*/];
// Fill in original array with array of strings
NSArray *newArray = [self prependArrayOfStrings:originalArray prefix:@"prefix"];