如何在Objective-C中声明一个字符串？

Question

如何向变量声明一个简单的字符串"test"？

Answer 1

AC字符串就像C中一样.

char myCString[] = "test";

NSString使用以下@字符:

NSString *myNSString = @"test";

如果您需要管理NSString的内存:

NSString *myNSString = [NSString stringWithFormat:@"test"];
NSString *myRetainedNSString = [[NSString alloc] initWithFormat:@"test"];

或者,如果您需要可编辑的字符串:

NSMutableString *myMutableString = [NSMutableString stringWithFormat:@"test"];

您可以从Apple NSString文档中了解更多信息.

Answer 2

NSString *testString = @"test";

Answer 3

标准字符串赋值可以这样完成:

NSString *myTestString = @"abc123";

除了基本分配之外,在使用标准字符[]数组没有的NSString类时,还有很多方法.这就是目标编程更好的原因!

例如,用一行代码填充带有html网页内容的字符串!**

创建和初始化字符串

+ string
– init
– initWithBytes:length:encoding:
– initWithBytesNoCopy:length:encoding:freeWhenDone:
– initWithCharacters:length:
– initWithCharactersNoCopy:length:freeWhenDone:
– initWithString:
– initWithCString:encoding:
– initWithUTF8String:
– initWithFormat:
– initWithFormat:arguments:
– initWithFormat:locale:
– initWithFormat:locale:arguments:
– initWithData:encoding:
+ stringWithFormat:
+ localizedStringWithFormat:
+ stringWithCharacters:length:
+ stringWithString:
+ stringWithCString:encoding:
+ stringWithUTF8String:

从文件创建和初始化字符串

+ stringWithContentsOfFile:encoding:error:
– initWithContentsOfFile:encoding:error:
+ stringWithContentsOfFile:usedEncoding:error:
– initWithContentsOfFile:usedEncoding:error:

从URL创建和初始化字符串

+ stringWithContentsOfURL:encoding:error:
– initWithContentsOfURL:encoding:error:
+ stringWithContentsOfURL:usedEncoding:error:
– initWithContentsOfURL:usedEncoding:error:

如果您需要一个字符串,您可以在其中编辑它想要查看的缓冲区:

NSMutableString