[Object C]_[初級]_[創建文件路徑時，已存在同名目錄和文件名的問題的解決方案]

原創

Foreveroriginal

2020-02-21 16:02

場景：導出數據到本地，以文件夾格式和文件名格式導出，數據中存在同名問題，爲了防止不覆蓋，要創建一個新的文件夾或者文件名用以區分同名的不同數據。

下面編寫一個小例子進行說明：

DirAndFile.h

#import <Foundation/Foundation.h>

@interface DirAndFile : NSObject

+(NSString*) getDirPathNewName:(NSString*)path;
+(NSString*) getFilePathNewName:(NSString*)path withPosfix:(NSString*)posfix;

@end

DirAndFile.m

#import "DirAndFile.h"

@implementation DirAndFile

//路徑中存在同名目錄，創建一個新的目錄名
+(NSString*) getDirPathNewName:(NSString*)path
{
    
    NSFileManager* manager = [NSFileManager defaultManager];
    
    NSString* tempPath =path;
    NSString* tempDirPath =@"";
    NSRange range = [path rangeOfString:@"/" options:NSBackwardsSearch];
    range.length = range.location;
    range.location = 0;
    tempDirPath = [path substringWithRange:range];
    
    //獲取目錄最後一個目錄名稱
    NSString* name=[path lastPathComponent];
    

    int count = 1;
    BOOL isDir =NO;
    
    while (true)
    {
        // 判斷目錄是否存在
        BOOL isExistDir =[manager fileExistsAtPath:tempPath isDirectory:&isDir];
        if (isDir && isExistDir)
        {
            if ([name rangeOfString:@"(" options:NSCaseInsensitiveSearch].location != NSNotFound)
            {
                NSRange range = [name rangeOfString:@"(" options:NSBackwardsSearch];
                range.length = range.location;
                range.location = 0;
                name = [name substringWithRange:range];
            }
            name =[name stringByAppendingFormat:@"(%d)",count];
            tempPath =[tempDirPath stringByAppendingPathComponent:name];
            isDir =NO;
            ++count;
            
        }
        else
        {
            break;
        }
        
    }
    return tempPath;
}
//路徑中存在同名文件名，創建一個新的文件名
+(NSString*) getFilePathNewName:(NSString*)path withPosfix:(NSString*)posfix
{
    NSAutoreleasePool *pool = [NSAutoreleasePool new];
    NSFileManager* manager = [NSFileManager defaultManager];
    int count = 1;
    
    NSRange range = [path rangeOfString:@"." options:NSBackwardsSearch];
    range.length = range.location;
    range.location = 0;
    NSString* namePart = [path substringWithRange:range];
    NSString* temp = namePart;
    while (YES)
    {
        temp = [temp stringByAppendingString:posfix];
        if (![manager fileExistsAtPath:temp])
        {
            [temp retain];
            break;
        }
        temp = [namePart stringByAppendingFormat:@"(%d)",count++];
    }
    [pool drain];
    return temp;
}

@end

main.m

#import <Foundation/Foundation.h>
#import "DirAndFile.h"


int main(int argc, const char * argv[]) {
    @autoreleasepool {
        //存在同名目錄名稱時，在目錄後添加一個數字標記區分同名目錄。
        NSString *dirPath =@"/Users/mac/work/test-dir(2)";
        NSFileManager *fm =[NSFileManager defaultManager];
        
        for (int i =0; i<5; ++i)
        {
            NSString *tempDir =[dirPath stringByAppendingPathComponent:@"aa"];
           tempDir= [DirAndFile getDirPathNewName:tempDir];
            [fm createDirectoryAtPath:tempDir withIntermediateDirectories:NO attributes:nil error:nil];
            NSLog(@"dir%d:%@",i+1,tempDir);
            
        }
        
        //存在同名文件名稱，文件名後添加數字標識
        FILE *file =NULL;
        for (int i =0; i<5; ++i)
        {
            NSString* filePath =[dirPath stringByAppendingPathComponent:@"content.txt"];
            filePath =[DirAndFile getFilePathNewName:filePath withPosfix:@".txt"];
            file =fopen([filePath UTF8String], "w");
            if (file == NULL)
            {
                break;
            }
            NSString *content=@"hello world";
            fwrite([content UTF8String], strlen([content UTF8String]), 1, file);
            fclose(file);
            
            

        }
        
    }
    return 0;
}

運行結果：