错误没有给出一个或多个必需参数的值

Question

使用以下代码找到每个匹配项时，我想将符合条件的完整Excel行添加到datagridview

例如，

通过将匹配找到的行号12传递给查询中的参数，但我收到一条错误消息

查找工作正常，但不会向private void B_General_Search_Click(object sender, EventArgs e) { Microsoft.Office.Interop.Excel.Application oXL = new Microsoft.Office.Interop.Excel.Application(); Microsoft.Office.Interop.Excel.Workbook oWB; Microsoft.Office.Interop.Excel.Range currentFind = null; Microsoft.Office.Interop.Excel.Range firstFind = null; string ConnStr = @"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + DefaultDirectory + @"\new29.xlsx" + ";Extended Properties=\"Excel 12.0 Xml;HDR=YES\";"; Thread.CurrentThread.CurrentCulture = new CultureInfo("en-US"); if (string.IsNullOrEmpty(TB_Search_Text.Text)) { MessageBox.Show("enter text for search"); return; } object missing = System.Reflection.Missing.Value; oWB = oXL.Workbooks.Open(DefaultDirectory + @"\new29.xlsx", //---Filename OR FilePath 0, //---object UpdateLinks true, //---object ReadOnly missing, //5//---object Format "", //---object Password "", //---object WriteResPassword false, //---object ReadOnlyRecommend Excel.XlPlatform.xlWindows, //---object Origin "", //---object Delimiter true, //---object Editable false, //---object Notify 0, //---object Converter true, //---object AddToMru false, //---object Local false); //---object CorruptLoad; //loop to search witin all excel sheets (workbook) foreach (Excel.Worksheet SheetID in oWB.Worksheets) { Excel.Range oRng = oXL.get_Range("A1", "XFD1048576"); currentFind = oRng.Find(TB_Search_Text.Text, missing, Excel.XlFindLookIn.xlValues, Excel.XlLookAt.xlPart, Excel.XlSearchOrder.xlByRows, Excel.XlSearchDirection.xlNext, false, missing, missing); while (currentFind != null) { //Keep track of the first range you find. if (firstFind == null) { firstFind = currentFind; } else if (currentFind.get_Address(true, true, Excel.XlReferenceStyle.xlR1C1) == firstFind.get_Address(true, true, Excel.XlReferenceStyle.xlR1C1)) { break; } currentFind = oRng.FindNext(currentFind); string cmdtxt = @"SELECT * FROM [" + SheetID.Name + "$] WHERE R=R12"; MessageBox.Show(cmdtxt); using (OleDbConnection conn = new OleDbConnection(ConnStr)) { OleDbDataAdapter DA = new OleDbDataAdapter(cmdtxt, conn); conn.Open(); //da.Parameters.Add(new OleDbParameter("@rowid", OleDbType.VarChar)).Value = "R12"; MessageBox.Show(cmdtxt); DA.Fill(dt); DGV_Data.DataSource = dt; conn.Close(); } } } oWB.Close(false, missing, missing); oWB = null; oXL.Quit(); }

添加任何内容

  

没有给出一个或多个必需参数的值。

                    string cmdtxt = @"SELECT * FROM [" + SheetID.Name + "$] WHERE R=@rowid";

                    MessageBox.Show(cmdtxt);

                    using (OleDbConnection conn = new OleDbConnection(ConnStr))
                    {
                        OleDbDataAdapter DA = new OleDbDataAdapter();
                        OleDbCommand cmd = new OleDbCommand(cmdtxt,conn);
                        cmd.Parameters.Add("@rowid", OleDbType.VarChar).Value = "R12";
                        DA.SelectCommand = cmd;
                        //conn.Open();

                        MessageBox.Show(cmdtxt);
                        DA.Fill(dt);
                        DGV_Data.DataSource = dt;
                        conn.Close();
                    }

我也试过这种方式

import { Component, OnInit } from '@angular/core';
import { BarComponent } from '../bar/bar.component';

@Component({
  selector: 'app-foo',
  templateUrl: './foo.component.html'
})
export class FooComponent implements OnInit {
  barComponentPath;

  constructor() { }

  ngOnInit() {
    this.barComponentPath = ""; // ?
  }
}