思路

将数据源拼成字符串，每组（行）数据用\n隔开，每组数据中每个数据之间用\t隔开，然后采用utf16的编码格式生成NSData类型的数据，存储为.xls后缀的文件。

姓名\t 年龄 \t身高\t体重\n
xxx1\t 19 \t 180\t56 \n
xxx2\t 20 \t 175\t78 \n

代码实现

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

@interface HJXLSManager : NSObject

/**
 *  @Author A, 2017-3-17 9:00:00
 *
 *  生成Excel文件
 *
 *  @param titles HJXLSTitleModle类型的数组，
 *   HJXLSTitleModle用于存储标题，和对应模型数据中的key
 *  
 *  @param datas 数据模型数组
 *
 *  @return BOOL 生成是否成功
 */

+(BOOL)createXLSFileTitles:(NSArray <HJXLSTitleModle *>*)titles datas:(NSArray *)datas fileName:(NSString *)name;

/**
 *  @Author A, 2017-3-17 9:00:00
 *
 *  通过名字获取ecel文件
 *
 *
 *  @return excel文件data数据
 */
+(NSData *)XLSFileWithFileName:(NSString *)Name;

+(NSString *)xlsFilePath;


@end


#import "HJBasicModle.h"

@interface HJXLSTitleModle : HJBasicModle
@property (nonatomic,copy) NSString *name;
@property (nonatomic,copy) NSString *key;

-(instancetype)initWithName:(NSString *)name key:(NSString *)key;
@end

titles也可以字典，字典key为模型的属性名，字典value为标题名称。因为字典是无序的，所以标题名称也是无序的，所以这里我采用数组存储这个标题名称。

#import "HJXLSManager.h"

@implementation HJXLSManager

+(NSString *)xlsFilePath{
    NSString *documentPath = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES).firstObject;
    NSString *xlsDirPath = [documentPath stringByAppendingPathComponent:@"xlsFile"];
    if (![[NSFileManager defaultManager] fileExistsAtPath:xlsDirPath]) {
        [[NSFileManager defaultManager] createDirectoryAtPath:xlsDirPath withIntermediateDirectories:YES attributes:nil error:nil];
    }
    return xlsDirPath;
}



+(BOOL)createXLSFileTitles:(NSArray <HJXLSTitleModle *>*)titles datas:(NSArray *)datas fileName:(NSString *)name{
    if (!titles) {
        return NO;
    }
    NSString *fileName = name?[name stringByAppendingString:@".xls"]:@"excel.xls";
    NSMutableArray *xlsDataMuArr = [NSMutableArray array];
    //插入标题
    for (HJXLSTitleModle *modle in titles) {
        [xlsDataMuArr addObject:modle.name];
        //插入制表符
        [xlsDataMuArr addObject:@"\t"];
    }
    //插入数据
    [xlsDataMuArr replaceObjectAtIndex:xlsDataMuArr.count-1 withObject:@"\n"];//换行
    for (id subData in datas) {
        for (HJXLSTitleModle *modle in titles) {
            NSString *objectString = [subData valueForKey:modle.key];
            [xlsDataMuArr addObject:[self XLSString:objectString]];
            [xlsDataMuArr addObject:@"\t"];
        }
        [xlsDataMuArr replaceObjectAtIndex:xlsDataMuArr.count-1 withObject:@"\n"];
    }
    NSString *xlsString = [xlsDataMuArr componentsJoinedByString:@""];
    NSData *xlsData = [xlsString dataUsingEncoding:NSUTF16StringEncoding];
    NSFileManager *fileManager = [NSFileManager defaultManager];
    return [fileManager createFileAtPath:[[self xlsFilePath] stringByAppendingPathComponent:fileName] contents:xlsData attributes:nil];
}

+(NSString *)XLSString:(NSString *)string{
    return string?:@"null";
}

+(NSData *)XLSFileWithFileName:(NSString *)Name{
    NSString *filePath = [[self xlsFilePath] stringByAppendingPathComponent:[Name stringByAppendingString:@".xls"]];
    return [[NSData alloc] initWithContentsOfFile:filePath];
}

@end

使用

 HJXLSTitleModle *modle1 = [[HJXLSTitleModle alloc] initWithName:@"名字" key:@"name"];
    HJXLSTitleModle *modle2 = [[HJXLSTitleModle alloc] initWithName:@"年龄" key:@"age"];
    HJXLSTitleModle *modle3 = [[HJXLSTitleModle alloc] initWithName:@"身高" key:@"height"];
    HJXLSTitleModle *modle4 = [[HJXLSTitleModle alloc] initWithName:@"体重" key:@"weight"];
    HJCeShiModle *dataModle1 = [[HJCeShiModle alloc] initWithName:@"xxx1" age:@"19" height:@"180" weight:@"56"];
    HJCeShiModle *dataModle2 = [[HJCeShiModle alloc] initWithName:@"xxx2" age:@"20" height:@"175" weight:@"78"];
    
    BOOL flag = [HJXLSManager createXLSFileTitles:@[modle1,modle2,modle3,modle4] datas:@[dataModle1,dataModle2] fileName:@"资料"];

生成的Excel文件如下：