我发现了像NPOI这样的软件包，但是我不知道如何流传输文件，或者在发送到asp.core之前如何将其转换为bit。我目前正在使用Angular 6
答案 0 :(得分：1)
您需要使用表单数据
HTML
<input accept=".xlsx,.csv" (change)="uploadFile($event)" type="file" #file />
TS
uploadFile(event) {
const file = event.target.files[0];
if (this.validateFile(file)) {
this.isUploadInprogress = true;
const formData: FormData = new FormData();
formData.append('files', file, file.name);
this.uploadService
.uploadFile(formData)
.subscribe(
uploadResponse => this.uploadSuccess(uploadResponse, file),
error => (this.isUploadInprogress = false)
);
} else {
this.invitationsService.showError('Please upload valid file');
}
}
答案 1 :(得分：0)
html ：（角度-> primeNg）
Ts：
onFileUpload(event) {
const file = event.files[0];
this.progressBar = true;
const formData: FormData = new FormData();
formData.append('file', file, file.name);
this.Service.importexcel(formData).subscribe(x => console.log(x));
}
asp api核心控制程序：您可以在等待后将其分隔在体系结构中...然后可以在检查正则表达式后将其从ienumerable发送到SQL。
[HttpPost("import", Name = "ImportExcel")]
public async Task<IActionResult> ImportExcel([FromForm]IFormFile file)
{
string folderName = "Upload";
string newPath = Path.Combine(Guid.NewGuid().ToString() +'_'+ folderName);
if (!Directory.Exists(newPath))
{
Directory.CreateDirectory(newPath);
}
string sFileExtension = Path.GetExtension(file.FileName).ToLower();
ISheet sheet;
string fullPath = Path.Combine(newPath, file.FileName);
var list = new List<ShipmentImportExcel>();
using (var stream = new FileStream(fullPath, FileMode.Create))
{
file.CopyTo(stream);
stream.Position = 0;
if (sFileExtension == ".xls")
{
HSSFWorkbook hssfwb = new HSSFWorkbook(stream); //This will read the Excel 97-2000 formats
sheet = hssfwb.GetSheetAt(0); //get first sheet from workbook
}
else
{
XSSFWorkbook hssfwb = new XSSFWorkbook(stream); //This will read 2007 Excel format
sheet = hssfwb.GetSheetAt(0); //get first sheet from workbook
}
IRow headerRow = sheet.GetRow(0); //Get Header Row
int cellCount = headerRow.LastCellNum;
for (int i = (sheet.FirstRowNum + 1); i <= sheet.LastRowNum; i++) //Read Excel File
{
var obj = new ExcelObject..();
IRow row = sheet.GetRow(i);
obj.property1 = row.GetCell(0).ToString();
obj.property2 = row.GetCell(1).ToString();
list.Add(obj);
}
}
return Ok(list);
}
答案 2 :(得分：0)
以下一些旧代码可能会有所帮助。请注意，添加了第一种方法是因为我发现将数据从Angular发送到控制器，进行处理然后再发送回去比在JavaScript中处理数据更快。
/// <summary>
/// Converts an uploaded Excel file (multipart) to a JSON object. Useful for converting large Excel files instead
/// of doing so in the browser, due to performance issues with SheetJS JavaScript library.
/// </summary>
[HttpPost]
[Route("ConvertedFile")]
[SwaggerResponse(HttpStatusCode.OK, "Success", typeof(List<Dictionary<string, object>>))]
public async Task<IHttpActionResult> GetConvertedFile()
{
var fileData = await processUploadFile();
fileData = removeEmptyRows(fileData);
return Ok(fileData);
}
/// <summary>
/// Converts an uploaded Excel file (multipart) to a JSON object. Sends the file to be processed.
/// </summary>
[HttpPost]
[Route("")]
[Authorize]
[SwaggerResponse(HttpStatusCode.OK, "Success")]
public Task<IHttpActionResult> UploadExcelFile()
{
var uploadFileData = await processUploadFile();
// Do something with uploadFileData...
return Ok();
}
/// <summary>
/// Processes the upload file by converting uploaded Excel file (XLSX) to "JSON" object.
/// </summary>
/// <returns></returns>
/// <exception cref="HttpResponseException"></exception>
private async Task<List<Dictionary<string, object>>> processUploadFile()
{
var documentData = new List<Dictionary<string, object>>();
if (!Request.Content.IsMimeMultipartContent())
{
throw new HttpResponseException(Request.CreateResponse(HttpStatusCode.UnsupportedMediaType));
}
try
{
Stopwatch sw = new Stopwatch();
sw.Start();
// Manage the multipart file in memory, not on the file system
MultipartMemoryStreamProvider streamProvider = new MultipartMemoryStreamProvider();
await Request.Content.ReadAsMultipartAsync(streamProvider);
// Should have only one "content" or file.
HttpContent content = streamProvider.Contents.FirstOrDefault();
// Convert the HttpContent to a Stream
using (Stream fileUploadStream = await content.ReadAsStreamAsync())
{
// Convert the Excel file stream to a List of "rows"
documentData = ExcelManager.ExcelDataReader(fileUploadStream);
if (documentData != null)
{
// header rows are not represented in the Values.
Log.Information("Order Data - Processed {0} lines of file data", documentData.Count);
}
else
{
Log.Warning("File processing error. No data.");
}
}
sw.Stop();
Log.Debug("Excel File took {0} ms", sw.ElapsedMilliseconds);
}
catch (Exception ex)
{
Log.Error(ex, string.Format("Test File Processing error."));
throw;
}
return documentData;
}
/// <summary>
/// Removes the empty rows.
/// </summary>
/// <param name="documentData">
/// Represent a list of excel rows. Each list item represent a row. Each Dictionary key represent the column
/// name. Dictionary value represent cell value.
/// </param>
/// <returns></returns>
private List<Dictionary<string, object>> removeEmptyRows(List<Dictionary<string, object>> documentData)
{
// build a new collection that only contains rows that have at least one column with a value
List<Dictionary<string, object>> nonEmptyRows = new List<Dictionary<string, object>>();
if (documentData != null && documentData.Count > 0)
{
// evaluate each item in the list
foreach (var item in documentData)
{
bool isRowEmpty = false;
// evaluate each Key/Value pair.
// RowID, State, and Message are the fields added to the document for state tracking.
// Do not consider those fields.
foreach (var key in item.Keys)
{
if (key != "RowID" && key != "State" && key != "Message")
{
var value = item[key];
Type type = value.GetType();
isRowEmpty = type.Name == "DBNull";
}
// if an non-null value is found within the current row then stop processing this item and
// continue on to the next item (excel row).
if (!isRowEmpty)
{
break;
}
}
// if the row has user supplied data then include it
if (!isRowEmpty)
{
nonEmptyRows.Add(item);
}
}
Log.Information("Removed {0} empty rows from excel File", documentData.Count - nonEmptyRows.Count);
}
return nonEmptyRows;
}
using Excel;
using Serilog;
using System;
using System.Collections.Generic;
using System.Data;
using System.IO;
using System.Linq;
public static class ExcelManager
{
/// <summary>
/// Read the steam file to convert it into a list of dictionaries
/// </summary>
/// <param name="fileUploadStream">The file stream</param>
/// <param name="columnNames">The column names to be read in the excel file</param>
/// <returns></returns>
public static List<Dictionary<string, object>> ExcelDataReader(Stream fileUploadStream)
{
List<Dictionary<string, object>> docData = new List<Dictionary<string, object>>();
IExcelDataReader excelReader = null;
try
{
excelReader = ExcelReaderFactory.CreateOpenXmlReader(fileUploadStream);
// Columns names are not handled
excelReader.IsFirstRowAsColumnNames = true;
bool isEmpty = isFileEmpty(excelReader);
if (!isEmpty)
{
// note: files that have only the header row will throw an exception when AsDataSet is called.
DataSet ds = excelReader.AsDataSet();
foreach (DataRow row in ds.Tables[0].Rows)
{
Dictionary<string, object> data = new Dictionary<string, object>();
foreach (DataColumn col in ds.Tables[0].Columns)
{
data[col.ColumnName] = row[col];
}
//This filter duplicates inserts with the same OrderLinkId
if ((docData.Exists(e => e.Values.ElementAt(0).Equals(data.Values.ElementAt(0)) && e.Values.ElementAt(1).Equals(data.Values.ElementAt(1))) == false))
{
docData.Add(data);
}
}
}
}
catch (Exception ex)
{
Log.Error(ex, "");
throw;
}
finally
{
excelReader.Close();
}
return docData;
}
/// <summary>
/// Verifies the file has at least one row of data. No header fields are used in the file.
/// </summary>
/// <param name="excelReader">The excel reader.</param>
/// <returns></returns>
private static bool isFileEmpty(IExcelDataReader excelReader)
{
try
{
while (excelReader.Read())
{
return false;
}
}
catch (Exception)
{
// swallow this exception.
}
return true;
}
}