宏:

// stringConcat(...)
//     A shortcut for concatenating strings (or objects' string representations).
//     Input: Any number of non-nil NSObjects.
//     Output: All arguments concatenated together into a single NSString.

#define stringConcat(...) \
    [@[__VA_ARGS__] componentsJoinedByString:@""]

测试用例:

- (void)testStringConcat {
    NSString *actual;

    actual = stringConcat(); //might not make sense, but it's still a valid expression.
    STAssertEqualObjects(@"", actual, @"stringConcat");

    actual = stringConcat(@"A");
    STAssertEqualObjects(@"A", actual, @"stringConcat");

    actual = stringConcat(@"A", @"B");
    STAssertEqualObjects(@"AB", actual, @"stringConcat");

    actual = stringConcat(@"A", @"B", @"C");
    STAssertEqualObjects(@"ABC", actual, @"stringConcat");

    // works on all NSObjects (not just strings):
    actual = stringConcat(@1, @" ", @2, @" ", @3);
    STAssertEqualObjects(@"1 2 3", actual, @"stringConcat");
}

备用宏:(如果你想强制一个最小数量的参数)

// stringConcat(...)
//     A shortcut for concatenating strings (or objects' string representations).
//     Input: Two or more non-nil NSObjects.
//     Output: All arguments concatenated together into a single NSString.

#define stringConcat(str1, str2, ...) \
    [@[ str1, str2, ##__VA_ARGS__] componentsJoinedByString:@""];

当我测试时，这两种格式都可以在XCode7中工作:

NSString *sTest1 = {@"This" " and that" " and one more"};
NSString *sTest2 = {
  @"This"
  " and that"
  " and one more"
};

NSLog(@"\n%@\n\n%@",sTest1,sTest2);

出于某种原因，您只需要在混合的第一个字符串上使用@操作符。

但是，它不能用于变量插入。为此，您可以使用这个极其简单的解决方案，除了对“cat”而不是“and”使用宏。

如何缩短stringByAppendingString和使用#define:

#define and stringByAppendingString

因此你可以使用:

NSString* myString = [@"Hello " and @"world"];

问题是它只适用于两个字符串，你需要包装额外的括号更多的追加:

NSString* myString = [[@"Hello" and: @" world"] and: @" again"];

我喜欢的方法是:

NSString *firstString = @"foo";
NSString *secondString = @"bar";
NSString *thirdString = @"baz";

NSString *joinedString = [@[firstString, secondString, thirdString] join];

你可以通过在NSArray中添加join方法来实现:

#import "NSArray+Join.h"
@implementation NSArray (Join)
-(NSString *)join
{
    return [self componentsJoinedByString:@""];
}
@end

@[]是NSArray的简短定义，我认为这是连接字符串最快的方法。

如果你不想使用类别，直接使用componentsJoinedByString:方法:

NSString *joinedString = [@[firstString, secondString, thirdString] componentsJoinedByString:@""];

NSString *label1 = @"Process Name: ";
NSString *label2 = @"Process Id: ";
NSString *processName = [[NSProcessInfo processInfo] processName];
NSString *processID = [NSString stringWithFormat:@"%d", [[NSProcessInfo processInfo] processIdentifier]];
NSString *testConcat = [NSString stringWithFormat:@"%@ %@ %@ %@", label1, processName, label2, processID];

如果你有两个NSString字面量，你也可以这样做:

NSString *joinedFromLiterals = @"ONE " @"MILLION " @"YEARS " @"DUNGEON!!!";

这对于加入#定义也很有用:

#define STRINGA @"Also, I don't know "
#define STRINGB @"where food comes from."
#define JOINED STRINGA STRINGB

享受。