23 KiB
QQ : 813100564 (MiniExcel讨论群) / 459050029 (dotnet china)
简介
MiniExcel简单、高效避免OOM的.NET处理Excel查、写、填充数据工具。
目前主流框架大多需要将数据全载入到内存方便操作,但这会导致内存消耗问题,MiniExcel 尝试以 Stream 角度写底层算法逻辑,能让原本1000多MB占用降低到几MB,避免内存不够情况。
特点
- 低内存耗用,避免OOM(out of memoery)、频繁 Full GC 情况
- 支持
即时
操作每行数据 - 兼具搭配 LINQ 延迟查询特性,能办到低消耗、快速分页等复杂查询
- 轻量,不依赖任何套件,DLL小于100KB
- 简便操作的 API 风格
快速开始
安装
请查看 from NuGet
更新日志
请查看 Release Notes
TODO
请查看 TODO
性能测试
以 Test1,000,000x10.xlsx 做基准与主流框架做性能测试,总共 1千万笔 "HelloWorld",文件大小 23 MB
Benchmarks 逻辑可以在 MiniExcel.Benchmarks 查看或是提交 PR,运行指令
dotnet run -p .\benchmarks\MiniExcel.Benchmarks\ -c Release -f netcoreapp3.1 -- -f * --join
最后一次运行结果 :
BenchmarkDotNet=v0.12.1, OS=Windows 10.0.19042
Intel Core i7-7700 CPU 3.60GHz (Kaby Lake), 1 CPU, 8 logical and 4 physical cores
[Host] : .NET Framework 4.8 (4.8.4341.0), X64 RyuJIT
Job-ZYYABG : .NET Framework 4.8 (4.8.4341.0), X64 RyuJIT
IterationCount=3 LaunchCount=3 WarmupCount=3
Method | 最大内存耗用 | 平均时间 | Gen 0 | Gen 1 | Gen 2 |
---|---|---|---|---|---|
'MiniExcel QueryFirst' | 0.109 MB | 726.4 us | - | - | - |
'ExcelDataReader QueryFirst' | 15.24 MB | 10,664,238.2 us | 566000.0000 | 1000.0000 | - |
'MiniExcel Query' | 17.3 MB | 14,179,334.8 us | 367000.0000 | 96000.0000 | 7000.0000 |
'ExcelDataReader Query' | 17.3 MB | 22,565,088.7 us | 1210000.0000 | 2000.0000 | - |
'Epplus QueryFirst' | 1,452 MB | 18,198,015.4 us | 535000.0000 | 132000.0000 | 9000.0000 |
'Epplus Query' | 1,451 MB | 23,647,471.1 us | 1451000.0000 | 133000.0000 | 9000.0000 |
'OpenXmlSDK Query' | 1,412 MB | 52,003,270.1 us | 978000.0000 | 353000.0000 | 11000.0000 |
'OpenXmlSDK QueryFirst' | 1,413 MB | 52,348,659.1 us | 978000.0000 | 353000.0000 | 11000.0000 |
'ClosedXml QueryFirst' | 2,158 MB | 66,188,979.6 us | 2156000.0000 | 575000.0000 | 9000.0000 |
'ClosedXml Query' | 2,184 MB | 191,434,126.6 us | 2165000.0000 | 577000.0000 | 10000.0000 |
Method | 最大内存耗用 | 平均时间 | Gen 0 | Gen 1 | Gen 2 |
---|---|---|---|---|---|
'MiniExcel Create Xlsx' | 15 MB | 11,531,819.8 us | 1020000.0000 | - | - |
'Epplus Create Xlsx' | 1,204 MB | 22,509,717.7 us | 1370000.0000 | 60000.0000 | 30000.0000 |
'OpenXmlSdk Create Xlsx' | 2,621 MB | 42,473,998.9 us | 1370000.0000 | 460000.0000 | 50000.0000 |
'ClosedXml Create Xlsx' | 7,141 MB | 140,939,928.6 us | 5520000.0000 | 1500000.0000 | 80000.0000 |
读 Excel
1. Query 查询 Excel 返回强型别
IEnumerable 数据 [Try it]
public class UserAccount
{
public Guid ID { get; set; }
public string Name { get; set; }
public DateTime BoD { get; set; }
public int Age { get; set; }
public bool VIP { get; set; }
public decimal Points { get; set; }
}
var rows = MiniExcel.Query<UserAccount>(path);
// or
using (var stream = File.OpenRead(path))
var rows = stream.Query<UserAccount>();
2. Query 查询 Excel 返回Dynamic
IEnumerable 数据 [Try it]
- Key 系统预设为
A,B,C,D...Z
MiniExcel | 1 |
---|---|
Github | 2 |
var rows = MiniExcel.Query(path).ToList();
// or
using (var stream = File.OpenRead(path))
{
var rows = stream.Query().ToList();
Assert.Equal("MiniExcel", rows[0].A);
Assert.Equal(1, rows[0].B);
Assert.Equal("Github", rows[1].A);
Assert.Equal(2, rows[1].B);
}
3. 查询数据以第一行数据当Key [Try it]
注意 : 同名以右边数据为准
Input Excel :
Column1 | Column2 |
---|---|
MiniExcel | 1 |
Github | 2 |
var rows = MiniExcel.Query(useHeaderRow:true).ToList();
// or
using (var stream = File.OpenRead(path))
{
var rows = stream.Query(useHeaderRow:true).ToList();
Assert.Equal("MiniExcel", rows[0].Column1);
Assert.Equal(1, rows[0].Column2);
Assert.Equal("Github", rows[1].Column1);
Assert.Equal(2, rows[1].Column2);
}
4. Query 查询支援延迟加载(Deferred Execution),能配合LINQ First/Take/Skip办到低消耗、高效率复杂查询
举例 : 查询第一笔数据
var row = MiniExcel.Query(path).First();
Assert.Equal("HelloWorld", row.A);
// or
using (var stream = File.OpenRead(path))
{
var row = stream.Query().First();
Assert.Equal("HelloWorld", row.A);
}
与其他框架效率比较 :
5. 查询指定 Sheet 名称
MiniExcel.Query(path, sheetName: "SheetName");
//or
stream.Query(sheetName: "SheetName");
6. 查询所有 Sheet 名称跟数据
var sheetNames = MiniExcel.GetSheetNames(path).ToList();
foreach (var sheetName in sheetNames)
{
var rows = MiniExcel.Query(path, sheetName: sheetName);
}
7. 查询所有栏(列)
var columns = MiniExcel.GetColumns(path); // e.g result : ["A","B"...]
var cnt = columns.Count; // get column count
8. Dynamic Query 转成 IDictionary<string,object>
数据
foreach(IDictionary<string,object> row in MiniExcel.Query(path))
{
//..
}
写 Excel
- 必须是非abstract 类别有公开无参数构造函数
- MiniExcel SaveAs 支援
IEnumerable参数延迟查询
,除非必要请不要使用 ToList 等方法读取全部数据到内存
图片 : 是否呼叫 ToList 的内存差别
1. Anonymous or strongly type [Try it]
var path = Path.Combine(Path.GetTempPath(), $"{Guid.NewGuid()}.xlsx");
MiniExcel.SaveAs(path, new[] {
new { Column1 = "MiniExcel", Column2 = 1 },
new { Column1 = "Github", Column2 = 2}
});
2. Datatable:
- 优先使用 Caption 当栏位名称
var path = Path.Combine(Path.GetTempPath(), $"{Guid.NewGuid()}.xlsx");
var table = new DataTable();
{
table.Columns.Add("Column1", typeof(string));
table.Columns.Add("Column2", typeof(decimal));
table.Rows.Add("MiniExcel", 1);
table.Rows.Add("Github", 2);
}
MiniExcel.SaveAs(path, table);
3. Dapper
using (var connection = GetConnection(connectionString))
{
var rows = connection.Query(@"select 'MiniExcel' as Column1,1 as Column2 union all select 'Github',2");
MiniExcel.SaveAs(path, rows);
}
4. IEnumerable<IDictionary<string, object>>
var values = new List<Dictionary<string, object>>()
{
new Dictionary<string,object>{{ "Column1", "MiniExcel" }, { "Column2", 1 } },
new Dictionary<string,object>{{ "Column1", "Github" }, { "Column2", 2 } }
};
MiniExcel.SaveAs(path, values);
output :
Column1 | Column2 |
---|---|
MiniExcel | 1 |
Github | 2 |
5. SaveAs 支援 Stream [Try it]
using (var stream = File.Create(path))
{
stream.SaveAs(values);
}
模板填充 Excel
- 宣告方式类似 Vue 模板
{{变量名称}}
, 或是集合渲染{{集合名称.栏位名称}}
- 集合渲染支持 IEnumerable/DataTable/DapperRow
1. 基本填充
代码:
// 1. By POCO
var value = new
{
Name = "Jack",
CreateDate = new DateTime(2021, 01, 01),
VIP = true,
Points = 123
};
MiniExcel.SaveAsByTemplate(path, templatePath, value);
// 2. By Dictionary
var value = new Dictionary<string, object>()
{
["Name"] = "Jack",
["CreateDate"] = new DateTime(2021, 01, 01),
["VIP"] = true,
["Points"] = 123
};
MiniExcel.SaveAsByTemplate(path, templatePath, value);
2. IEnumerable 数据填充
Note1: 同行从左往右以第一个 IEnumerableUse 当列表来源 (不支持同列多集合)
代码:
//1. By POCO
var value = new
{
employees = new[] {
new {name="Jack",department="HR"},
new {name="Lisa",department="HR"},
new {name="John",department="HR"},
new {name="Mike",department="IT"},
new {name="Neo",department="IT"},
new {name="Loan",department="IT"}
}
};
MiniExcel.SaveAsByTemplate(path, templatePath, value);
//2. By Dictionary
var value = new Dictionary<string, object>()
{
["employees"] = new[] {
new {name="Jack",department="HR"},
new {name="Lisa",department="HR"},
new {name="John",department="HR"},
new {name="Mike",department="IT"},
new {name="Neo",department="IT"},
new {name="Loan",department="IT"}
}
};
MiniExcel.SaveAsByTemplate(path, templatePath, value);
3. 复杂数据填充
Note: 支持多 sheet 填充,并共用同一组参数
模板:
最终效果:
代码:
// 1. By POCO
var value = new
{
title = "FooCompany",
managers = new[] {
new {name="Jack",department="HR"},
new {name="Loan",department="IT"}
},
employees = new[] {
new {name="Wade",department="HR"},
new {name="Felix",department="HR"},
new {name="Eric",department="IT"},
new {name="Keaton",department="IT"}
}
};
MiniExcel.SaveAsByTemplate(path, templatePath, value);
// 2. By Dictionary
var value = new Dictionary<string, object>()
{
["title"] = "FooCompany",
["managers"] = new[] {
new {name="Jack",department="HR"},
new {name="Loan",department="IT"}
},
["employees"] = new[] {
new {name="Wade",department="HR"},
new {name="Felix",department="HR"},
new {name="Eric",department="IT"},
new {name="Keaton",department="IT"}
}
};
MiniExcel.SaveAsByTemplate(path, templatePath, value);
4. 大数据填充效率比较
NOTE: 在 MiniExcel 使用 IEnumerable 延迟 ( 不ToList ) 可以节省内存使用
5. Cell 值自动类别对应
模板
最终效果
类别
public class Poco
{
public string @string { get; set; }
public int? @int { get; set; }
public decimal? @decimal { get; set; }
public double? @double { get; set; }
public DateTime? datetime { get; set; }
public bool? @bool { get; set; }
public Guid? Guid { get; set; }
}
代码
var poco = new TestIEnumerableTypePoco { @string = "string", @int = 123, @decimal = decimal.Parse("123.45"), @double = (double)123.33, @datetime = new DateTime(2021, 4, 1), @bool = true, @Guid = Guid.NewGuid() };
var value = new
{
Ts = new[] {
poco,
new TestIEnumerableTypePoco{},
null,
poco
}
};
MiniExcel.SaveAsByTemplate(path, templatePath, value);
6. Example : 列出 Github 专案
模板
最终效果
代码
var projects = new[]
{
new {Name = "MiniExcel",Link="https://github.com/shps951023/MiniExcel",Star=146, CreateTime=new DateTime(2021,03,01)},
new {Name = "HtmlTableHelper",Link="https://github.com/shps951023/HtmlTableHelper",Star=16, CreateTime=new DateTime(2020,02,01)},
new {Name = "PocoClassGenerator",Link="https://github.com/shps951023/PocoClassGenerator",Star=16, CreateTime=new DateTime(2019,03,17)}
};
var value = new
{
User = "ITWeiHan",
Projects = projects,
TotalStar = projects.Sum(s => s.Star)
};
MiniExcel.SaveAsByTemplate(path, templatePath, value);
Excel Column Name/Index/Ignore Attribute
e.g
input excel :
public class ExcelAttributeDemo
{
[ExcelColumnName("Column1")]
public string Test1 { get; set; }
[ExcelColumnName("Column2")]
public string Test2 { get; set; }
[ExcelIgnore]
public string Test3 { get; set; }
[ExcelColumnIndex("I")] // system will convert "I" to 8 index
public string Test4 { get; set; }
public string Test5 { get; } //wihout set will ignore
public string Test6 { get; private set; } //un-public set will ignore
[ExcelColumnIndex(3)] // start with 0
public string Test7 { get; set; }
}
var rows = MiniExcel.Query<ExcelAttributeDemo>(path).ToList();
Assert.Equal("Column1", rows[0].Test1);
Assert.Equal("Column2", rows[0].Test2);
Assert.Null(rows[0].Test3);
Assert.Equal("Test7", rows[0].Test4);
Assert.Null(rows[0].Test5);
Assert.Null(rows[0].Test6);
Assert.Equal("Test4", rows[0].Test7);
Excel 类别自动判断
MiniExcel 预设会根据扩展名或是 Stream 类别判断是 xlsx 还是 csv,但会有失准时候,请自行指定。
stream.SaveAs(excelType:ExcelType.CSV);
//or
stream.SaveAs(excelType:ExcelType.XLSX);
//or
stream.Query(excelType:ExcelType.CSV);
//or
stream.Query(excelType:ExcelType.XLSX);
范例
1. SQLite & Dapper 读取大数据新增到数据库
note : 请不要呼叫 call ToList/ToArray 等方法,这会将所有数据读到内存内
using (var connection = new SQLiteConnection(connectionString))
{
connection.Open();
using (var transaction = connection.BeginTransaction())
using (var stream = File.OpenRead(path))
{
var rows = stream.Query();
foreach (var row in rows)
connection.Execute("insert into T (A,B) values (@A,@B)", new { row.A, row.B }, transaction: transaction);
transaction.Commit();
}
}
2. ASP.NET Core 3.1 or MVC 5 下载 Excel Xlsx API Demo Try it
public class HomeController : Controller
{
public IActionResult Index()
{
return new ContentResult
{
ContentType = "text/html",
StatusCode = (int)HttpStatusCode.OK,
Content = @"<html><body>
<a href='Home/DownloadExcel'>DownloadExcel</a><br>
<a href='Home/DownloadExcelFromTemplatePath'>DownloadExcelFromTemplatePath</a><br>
<a href='Home/DownloadExcelFromTemplateBytes'>DownloadExcelFromTemplateBytes</a>
</body></html>"
};
}
public IActionResult DownloadExcel()
{
var values = new[] {
new { Column1 = "MiniExcel", Column2 = 1 },
new { Column1 = "Github", Column2 = 2}
};
var memoryStream = new MemoryStream();
memoryStream.SaveAs(values);
memoryStream.Seek(0, SeekOrigin.Begin);
return new FileStreamResult(memoryStream, "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet")
{
FileDownloadName = "demo.xlsx"
};
}
public IActionResult DownloadExcelFromTemplatePath()
{
string templatePath = "TestTemplateComplex.xlsx";
Dictionary<string, object> value = new Dictionary<string, object>()
{
["title"] = "FooCompany",
["managers"] = new[] {
new {name="Jack",department="HR"},
new {name="Loan",department="IT"}
},
["employees"] = new[] {
new {name="Wade",department="HR"},
new {name="Felix",department="HR"},
new {name="Eric",department="IT"},
new {name="Keaton",department="IT"}
}
};
MemoryStream memoryStream = new MemoryStream();
memoryStream.SaveAsByTemplate(templatePath, value);
memoryStream.Seek(0, SeekOrigin.Begin);
return new FileStreamResult(memoryStream, "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet")
{
FileDownloadName = "demo.xlsx"
};
}
private static Dictionary<string, Byte[]> TemplateBytesCache = new Dictionary<string, byte[]>();
static HomeController()
{
string templatePath = "TestTemplateComplex.xlsx";
byte[] bytes = System.IO.File.ReadAllBytes(templatePath);
TemplateBytesCache.Add(templatePath, bytes);
}
public IActionResult DownloadExcelFromTemplateBytes()
{
byte[] bytes = TemplateBytesCache["TestTemplateComplex.xlsx"];
Dictionary<string, object> value = new Dictionary<string, object>()
{
["title"] = "FooCompany",
["managers"] = new[] {
new {name="Jack",department="HR"},
new {name="Loan",department="IT"}
},
["employees"] = new[] {
new {name="Wade",department="HR"},
new {name="Felix",department="HR"},
new {name="Eric",department="IT"},
new {name="Keaton",department="IT"}
}
};
MemoryStream memoryStream = new MemoryStream();
memoryStream.SaveAsByTemplate(bytes, value);
memoryStream.Seek(0, SeekOrigin.Begin);
return new FileStreamResult(memoryStream, "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet")
{
FileDownloadName = "demo.xlsx"
};
}
}
3. 分页查询
void Main()
{
var rows = MiniExcel.Query(path);
Console.WriteLine("==== No.1 Page ====");
Console.WriteLine(Page(rows,pageSize:3,page:1));
Console.WriteLine("==== No.50 Page ====");
Console.WriteLine(Page(rows,pageSize:3,page:50));
Console.WriteLine("==== No.5000 Page ====");
Console.WriteLine(Page(rows,pageSize:3,page:5000));
}
public static IEnumerable<T> Page<T>(IEnumerable<T> en, int pageSize, int page)
{
return en.Skip(page * pageSize).Take(pageSize);
}
FQA
Q: 如何将查询结果转为 DataTable
提醒 : 不建议使用,因为DataTable会将数据全载入内存
,失去MiniExcel低内存消耗功能。
public static DataTable QueryAsDataTable(string path)
{
var rows = MiniExcel.Query(path, true);
var dt = new DataTable();
var first = true;
foreach (IDictionary<string, object> row in rows)
{
if (first)
{
foreach (var key in row.Keys)
{
var type = row[key]?.GetType() ?? typeof(string);
dt.Columns.Add(key, type);
}
first = false;
}
dt.Rows.Add(row.Values.ToArray());
}
return dt;
}
Q: Excel 表头标题名称跟 class 属性名称不一致,如何对应?
A. 请使用 ExcelColumnName 作 mapping
局限与警告
- 目前不支援 xls (97-2003) 或是加密文件。
参考
- 读取逻辑 : ExcelDataReader / ClosedXML
- API 设计方式 : StackExchange/Dapper