无法将类型'double'隐式转换为'double []' [英] Cannot implicitly convert type 'double' to 'double[]'

问题描述

  protected   void  btnSubmit_Click（对象发​​件人，EventArgs e）
 {
  string  connectionString =   ; 
  if （FileUpload1.HasFile）
 {
  string  fileName = Path.GetFileName（FileUpload1.PostedFile.FileName）; 
  string  fileExtension = Path.GetExtension（FileUpload1.PostedFile.FileName）; 
  string  fileLocation = Server.MapPath（  〜/ App_Data / + fileName）; 
 FileUpload1.SaveAs（fileLocation）; 
  if （fileExtension ==  。xls ）
 {
 connectionString =   Provider = Microsoft.Jet.OLEDB。 4.0;数据源= + fileLocation +  ;扩展属性= \Excel 8.0; HDR =是; IMEX = 2\ ; 
} 
  else   if （fileExtension ==  。xlsx）
 {
 connectionString =   Provider = Microsoft.ACE.OLEDB.12.0; Data Source = + fileLocation +  ;扩展属性= \Excel 12.0; HDR =是; IMEX = 2 \; 
} 
 OleDbConnection con =  new  OleDbConnection（connectionString）; 
 OleDbCommand cmd =  new  OleDbCommand（）; 
 ArrayList List =  new  ArrayList（）; 
 cmd.CommandType = System.Data.CommandType.Text; 
 cmd.Connection = con; 
 OleDbDataAdapter dAdapter =  new  OleDbDataAdapter（cmd）; 
 DataTable dtExcelRecords =  new  DataTable（）; 
 con.Open（）; 
 DataTable dtExcelSheetName = con.GetOleDbSchemaTable（OleDbSchemaGuid.Tables， null ）; 
  string  getExcelSheetName = dtExcelSheetName.Rows [ 0 ] [  Table_Name]。ToString（）; 
 cmd.CommandText =   SELECT * FROM [ + getExcelSheetName +  ]; 
 dAdapter.SelectCommand = cmd; 
 dAdapter.Fill（dtExcelRecords）; 
  if （会话[  dtInSession]！=  null ）
 {
 dt =（DataTable）Session [  dtInSession]; 
} 
  for （ int  i =  0 ; i <  dtExcelRecords.Rows.Count; i ++）
 {
  int 结果; 
  //  如果你想得到字符串 
 DataRow thisRow =（DataRow ）dtExcelRecords.Rows [I]; 
  double  [] X = Convert.ToDouble（thisRow [  Y]）; 
  double  [] Y = Convert.ToDouble（thisRow [  X]）; 
} 

解决方案

替换下面的行...

  double  [] X = Convert.ToDouble（thisRow [  Y]）; 
  double  [] Y = Convert.ToDouble（thisRow [  X]）; 

with

  double  X = Convert.ToDouble（thisRow [  Y] ）; 
  double  Y = Convert.ToDouble（thisRow [  X]）; 

protected void btnSubmit_Click(object sender, EventArgs e)
{
    string connectionString = "";
    if (FileUpload1.HasFile)
    {
        string fileName = Path.GetFileName(FileUpload1.PostedFile.FileName);
        string fileExtension = Path.GetExtension(FileUpload1.PostedFile.FileName);
        string fileLocation = Server.MapPath("~/App_Data/" + fileName);
        FileUpload1.SaveAs(fileLocation);
        if (fileExtension == ".xls")
        {
            connectionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + fileLocation + ";Extended Properties=\"Excel 8.0;HDR=Yes;IMEX=2\"";
        }
        else if (fileExtension == ".xlsx")
        {
            connectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + fileLocation + ";Extended Properties=\"Excel 12.0;HDR=Yes;IMEX=2\"";
        }
        OleDbConnection con = new OleDbConnection(connectionString);
        OleDbCommand cmd = new OleDbCommand();
        ArrayList List = new ArrayList();
        cmd.CommandType = System.Data.CommandType.Text;
        cmd.Connection = con;
        OleDbDataAdapter dAdapter = new OleDbDataAdapter(cmd);
        DataTable dtExcelRecords = new DataTable();
        con.Open();
        DataTable dtExcelSheetName = con.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, null);
        string getExcelSheetName = dtExcelSheetName.Rows[0]["Table_Name"].ToString();
        cmd.CommandText = "SELECT * FROM [" + getExcelSheetName + "]";
        dAdapter.SelectCommand = cmd;
        dAdapter.Fill(dtExcelRecords);
        if (Session["dtInSession"] != null)
        {
            dt = (DataTable)Session["dtInSession"];
        }
        for (int i = 0; i < dtExcelRecords.Rows.Count; i++)
        {
           int result;
            //if you want to get the string
          DataRow thisRow = (DataRow)dtExcelRecords.Rows[i];
          double[] X = Convert.ToDouble(thisRow["Y"]);
          double[] Y = Convert.ToDouble(thisRow["X"]);   
        }

解决方案

Replace below lines...

double[] X = Convert.ToDouble(thisRow["Y"]);
double[] Y = Convert.ToDouble(thisRow["X"]);

with

double X = Convert.ToDouble(thisRow["Y"]);
double Y = Convert.ToDouble(thisRow["X"]); 

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