31 KiB
Introduction
MiniExcel is simple and efficient to avoid OOM's .NET processing Excel tool.
At present, most popular frameworks need to load all the data into the memory to facilitate operation, but it will cause memory consumption problems. MiniExcel tries to use algorithm from a stream to reduce the original 1000 MB occupation to a few MB to avoid OOM(out of memory).
Features
- Low memory consumption, avoid OOM (out of memory) and full GC
- Support
real-time
operation of each row of data - Support LINQ deferred execution, it can do low-consumption, fast paging and other complex queries
- Lightweight, without Microsoft Office installed, no COM+, third-party dependencies, DLL size is less than 100KB
- Easy API style to read/write/fill excel
Get Started
Installation
You can install the package from NuGet
Release Notes
Please Check Release Notes
TODO
Please Check TODO
Performance
Test1,000,000x10.xlsx as performance test basic file,A total of 10,000,000 "HelloWorld" with a file size of 23 MB
Benchmarks logic can be found in MiniExcel.Benchmarks , and test cli
dotnet run -p .\benchmarks\MiniExcel.Benchmarks\ -c Release -f netcoreapp3.1 -- -f * --join
Output from the latest run is :
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 | Max Memory Usage | Mean | 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 | Max Memory Usage | Mean | 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 |
Excel Query
1. Execute a query and map the results to a strongly typed IEnumerable [Try it]
Recommand to use Stream.Query because of better efficiency.
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. Execute a query and map it to a list of dynamic objects without using head [Try it]
- dynamic key is
A.B.C.D..
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. Execute a query with first header row [Try it]
note : same column name use last right one
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 Support LINQ Extension First/Take/Skip ...etc
Query First
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);
}
Performance between MiniExcel/ExcelDataReader/ClosedXML/EPPlus
5. Query by sheet name
MiniExcel.Query(path, sheetName: "SheetName");
//or
stream.Query(sheetName: "SheetName");
6. Query all sheet name and rows
var sheetNames = MiniExcel.GetSheetNames(path).ToList();
foreach (var sheetName in sheetNames)
{
var rows = MiniExcel.Query(path, sheetName: sheetName);
}
7. Get Columns
var columns = MiniExcel.GetColumns(path); // e.g result : ["A","B"...]
var cnt = columns.Count; // get column count
8. Dynamic Query cast row to IDictionary<string,object>
foreach(IDictionary<string,object> row in MiniExcel.Query(path))
{
//..
}
9. Query Query Excel return DataTable
Not recommended, because DataTable will load all data into memory and lose MiniExcel's low memory consumption feature.
var table = MiniExcel.QueryAsDataTable(path, useHeaderRow: true);
10. Specify the cell to start reading data
MiniExcel.Query(path,useHeaderRow:true,startCell:"B3")
11. Fill Merged Cells
Note: The efficiency is slower compared to not using merge fill
Reason: The OpenXml standard puts mergeCells at the bottom of the file, which leads to the need to foreach the sheetxml twice
var config = new OpenXmlConfiguration()
{
FillMergedCells = true
};
var rows = MiniExcel.Query(path, configuration: config);
support variable length and width multi-row and column filling
Create Excel
-
Must be a non-abstract type with a public parameterless constructor .
-
MiniExcel support parameter IEnumerable Deferred Execution, If you want to use least memory, please do not call methods such as ToList
e.g : ToList or not memory usage
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
- DataTable use Caption for column name first, then use columname
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);
Create File Result :
Column1 | Column2 |
---|---|
MiniExcel | 1 |
Github | 2 |
5. SaveAs Stream [Try it]
using (var stream = File.Create(path))
{
stream.SaveAs(values);
}
5. SaveAs to MemoryStream [Try it]
using (var stream = new MemoryStream()) //support FileStream,MemoryStream ect.
{
stream.SaveAs(values);
}
e.g : api of export excel
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"
};
}
6. Support IDataReader value parameter
MiniExcel.SaveAs(path, reader);
7. Create Multiple Sheets
// 1. Dictionary<string,object>
var users = new[] { new { Name = "Jack", Age = 25 }, new { Name = "Mike", Age = 44 } };
var department = new[] { new { ID = "01", Name = "HR" }, new { ID = "02", Name = "IT" } };
var sheets = new Dictionary<string, object>
{
["users"] = users,
["department"] = department
};
MiniExcel.SaveAs(path, sheets);
// 2. DataSet
var sheets = new DataSet();
sheets.Add(UsersDataTable);
sheets.Add(DepartmentDataTable);
//..
MiniExcel.SaveAs(path, sheets);
8. TableStyles Options
From the v0.15.0 version, the default style has been changed to
Without style configuration
var config = new OpenXmlConfiguration()
{
TableStyles = TableStyles.None
};
MiniExcel.SaveAs(path, value,configuration:config);
Fill Data To Excel Template
- The declaration is similar to Vue template
{{variable name}}
, or the collection rendering{{collection name.field name}}
- Collection rendering support IEnumerable/DataTable/DapperRow
1. Basic Fill
Code:
// 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 Data Fill
Note1: Use the first IEnumerable of the same column as the basis for filling list
Code:
//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. Complex Data Fill
Note: Support multi-sheets and using same varible
Template:
Result:
// 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. Fill Big Data Performance
NOTE: Using IEnumerable deferred execution not ToList can save max memory usage in MiniExcel
5. Cell value auto mapping type
Template
Result
Class
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; }
}
Code
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 : List Github Projects
Template
Result
Code
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);
7. DataTable as parameter
var managers = new DataTable();
{
managers.Columns.Add("name");
managers.Columns.Add("department");
managers.Rows.Add("Jack", "HR");
managers.Rows.Add("Loan", "IT");
}
var value = new Dictionary<string, object>()
{
["title"] = "FooCompany",
["managers"] = managers,
};
MiniExcel.SaveAsByTemplate(path, templatePath, value);
Excel Column Name/Index/Ignore Attribute
1. Specify the column name, column index, column ignore
Excel Example
Code
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);
2. Custom DateTime Format (ExcelFormatAttribute)
Class
public class Dto
{
public string Name { get; set; }
[ExcelFormat("MMMM dd, yyyy")]
public DateTime InDate { get; set; }
}
Code
var value = new Dto[] {
new Issue241Dto{ Name="Jack",InDate=new DateTime(2021,01,04)},
new Issue241Dto{ Name="Henry",InDate=new DateTime(2020,04,05)},
};
MiniExcel.SaveAs(path, value);
Result
Query supports custom format conversion
Excel Type Auto Check
- MiniExcel will check whether it is xlsx or csv based on the
file extension
by default, but there may be inaccuracy, please specify it manually. - Stream cannot be know from which excel, please specify it manually.
stream.SaveAs(excelType:ExcelType.CSV);
//or
stream.SaveAs(excelType:ExcelType.XLSX);
//or
stream.Query(excelType:ExcelType.CSV);
//or
stream.Query(excelType:ExcelType.XLSX);
Examples:
1. SQLite & Dapper Large Size File
SQL Insert Avoid OOM
note : please don't call ToList/ToArray methods after Query, it'll load all data into memory
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 Download/Upload Excel Xlsx API Demo Try it
public class ApiController : Controller
{
public IActionResult Index()
{
return new ContentResult
{
ContentType = "text/html",
StatusCode = (int)HttpStatusCode.OK,
Content = @"<html><body>
<a href='api/DownloadExcel'>DownloadExcel</a><br>
<a href='api/DownloadExcelFromTemplatePath'>DownloadExcelFromTemplatePath</a><br>
<a href='api/DownloadExcelFromTemplateBytes'>DownloadExcelFromTemplateBytes</a><br>
<p>Upload Excel</p>
<form method='post' enctype='multipart/form-data' action='/api/uploadexcel'>
<input type='file' name='excel'> <br>
<input type='submit' >
</form>
</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 ApiController()
{
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"
};
}
public IActionResult UploadExcel(IFormFile excel)
{
var stream = new MemoryStream();
excel.CopyTo(stream);
foreach (var item in stream.Query(true))
{
// do your logic etc.
}
return Ok("File uploaded successfully");
}
}
3. Paging Query
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);
}
4. WebForm export Excel by memorystream
var fileName = "Demo.xlsx";
var sheetName = "Sheet1";
HttpResponse response = HttpContext.Current.Response;
response.Clear();
response.ContentType = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet";
response.AddHeader("Content-Disposition", $"attachment;filename=\"{fileName}\"");
var values = new[] {
new { Column1 = "MiniExcel", Column2 = 1 },
new { Column1 = "Github", Column2 = 2}
};
var memoryStream = new MemoryStream();
memoryStream.SaveAs(values, sheetName: sheetName);
memoryStream.Seek(0, SeekOrigin.Begin);
memoryStream.CopyTo(Response.OutputStream);
response.End();
5. i18n multi-language and role authority management
Like the example, create a method to handle i18n and permission management, and use yield return to return IEnumerable<Dictionary<string, object>>
to achieve dynamic and low-memory processing effects
void Main()
{
var value = new Order[] {
new Order(){OrderNo = "SO01",CustomerID="C001",ProductID="P001",Qty=100,Amt=500},
new Order(){OrderNo = "SO02",CustomerID="C002",ProductID="P002",Qty=300,Amt=400},
};
Console.WriteLine("en-Us and Sales role");
{
var path = Path.GetTempPath() + Guid.NewGuid() + ".xlsx";
var lang = "en-US";
var role = "Sales";
MiniExcel.SaveAs(path, GetOrders(lang, role, value));
MiniExcel.Query(path, true).Dump();
}
Console.WriteLine("zh-CN and PMC role");
{
var path = Path.GetTempPath() + Guid.NewGuid() + ".xlsx";
var lang = "zh-CN";
var role = "PMC";
MiniExcel.SaveAs(path, GetOrders(lang, role, value));
MiniExcel.Query(path, true).Dump();
}
}
private IEnumerable<Dictionary<string, object>> GetOrders(string lang, string role, Order[] orders)
{
foreach (var order in orders)
{
var newOrder = new Dictionary<string, object>();
if (lang == "zh-CN")
{
newOrder.Add("客户编号", order.CustomerID);
newOrder.Add("订单编号", order.OrderNo);
newOrder.Add("产品编号", order.ProductID);
newOrder.Add("数量", order.Qty);
if (role == "Sales")
newOrder.Add("价格", order.Amt);
yield return newOrder;
}
else if (lang == "en-US")
{
newOrder.Add("Customer ID", order.CustomerID);
newOrder.Add("Order No", order.OrderNo);
newOrder.Add("Product ID", order.ProductID);
newOrder.Add("Quantity", order.Qty);
if (role == "Sales")
newOrder.Add("Amount", order.Amt);
yield return newOrder;
}
else
{
throw new InvalidDataException($"lang {lang} wrong");
}
}
}
public class Order
{
public string OrderNo { get; set; }
public string CustomerID { get; set; }
public decimal Qty { get; set; }
public string ProductID { get; set; }
public decimal Amt { get; set; }
}
FAQ
Q: Excel header title not equal class property name, how to mapping?
A. Please use ExcelColumnName attribute
Q. How to query or export multiple-sheets?
A. GetSheetNames
method with Query sheetName parameter.
var sheets = MiniExcel.GetSheetNames(path);
foreach (var sheet in sheets)
{
Console.WriteLine($"sheet name : {sheet} ");
var rows = MiniExcel.Query(path,useHeaderRow:true,sheetName:sheet);
Console.WriteLine(rows);
}
Q. How to mapping enum?
A. Be sure excel & property name same, system will auto mapping (case insensitive)
Q. Whether to use Count will load all data into the memory?
No, the image test has 1 million rows*10 columns of data, the maximum memory usage is <60MB, and it takes 13.65 seconds
Limitations and caveats
- Not support xls and encrypted file now
- xlsm only support Query