@interface ReplaceStringInDirectory : NSObject
/***  替换指定文件中指定的所有字符串为另一个字符串*/
+ (void)replaceInDirectory:(NSString *)pathFile withOldString:(NSString *)oldString withNewString:(NSString *)newString;//替换指定目录下所有指定类型的文件中的字符串
+ (void)replaceInDirectory:(NSString *)pathDirectory withOldString:(NSString *)oldString withNewString:(NSString *)newString InType:(NSString *)typeFile;
@end

/***  替换指定文件中指定的所有字符串为另一个字符串*/
+ (void)replaceInDirectory:(NSString *)pathFile withOldString:(NSString *)oldString withNewString:(NSString *)newString
{//文件目录管理器 一个单例对象NSFileManager *fm = [NSFileManager defaultManager];//先备份一份文件在相同的路劲下，并以指定文件格式[fm copyItemAtPath:pathFile toPath:[pathFile stringByAppendingString:@"_bak"] error:nil];//创建文件句柄 文件指针 用以操作文件的内容NSFileHandle *fh = [NSFileHandle fileHandleForUpdatingAtPath:pathFile];//读取文件的信息NSData *data = [fh readDataToEndOfFile];  //这样会使的当前文件指针fh指向末尾NSString *dataString = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];//判断当前字符串对象中是否包含有oldWordif ([dataString containsString:oldString]) {dataString = [dataString stringByReplacingOccurrencesOfString:oldString withString:newString];}//将文件清空，之后将字符串写回到文件中[fh truncateFileAtOffset:0];[fh writeData:[dataString dataUsingEncoding:NSUTF8StringEncoding]];//同步文件。  关闭线程锁
    [fh synchronizeFile];[fh closeFile];
}//替换指定目录下所有指定类型的文件中的字符串
+ (void)replaceInDirectory:(NSString *)pathDirectory withOldString:(NSString *)oldString withNewString:(NSString *)newString InType:(NSString *)typeFile
{NSFileManager *fm = [NSFileManager defaultManager];//深层次的遍历目录NSArray *arrayFile = [fm subpathsOfDirectoryAtPath:pathDirectory error:nil];for (NSString *item in arrayFile) {//获取文件的后缀名if ([typeFile isEqualToString:[item pathExtension]]) {[self replaceInDirectory:[pathDirectory stringByAppendingFormat:@"/%@",item] withOldString:oldString withNewString:newString];}}
}