IOS-txt文件UTF8、UTF16格式

在- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions中添加如下测试：

NSString* path = [[NSBundlemainBundle] pathForResource:@"textfile"ofType:@"txt"];

    NSStringEncoding enc = NSUTF8StringEncoding; // this is a lie, so an error will result later 

    NSError* err; 

    // attempt to load a text file while specifying the wrong encoding

    NSString* s = [NSStringstringWithContentsOfFile:path encoding:enc error:&err];

    // at this point, s is nil as a signal that things went wrong, and err is a meaningful NSError

    if (nil == s) // could also say if (!s)

    {

        NSLog(@"We got an error, as expected; it says:\n\"%@\"", [err localizedDescription]);

    }

    else

    {

        NSLog(@"everything went just fine; the text file says:\n%@", s); 

        // change NSUTF8StringEncoding to NSUTF16StringEncoding to get this message!

    }

显示的提示信息：（此txt文档是UTF16格式的，使用UTF8读不出来）

We got an error, as expected; it says:

"The operation couldn’t be completed. (Cocoa error 261.)"

改为NSUTF16StringEncoding 后即可读出数据：

everything went just fine; the text file says:

This file in UTF16 encoding, but the app is going to claim it's UTF8.

 

 TXT格式有四种编码：ANSI,Unicode,Unicode big endian,UTF-8。