如何在Windows应用程序中使用C＃从datagridview删除行

Question

I have a database in xml my xml file is:

      <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
          <!--This is an XML Generated File-->
       <Categories>
         <Category>
          <CategoryId>1</CategoryId>
          <CategoryName>jitu</CategoryName>
         </Category>
         <Category>
          <CategoryId>2</CategoryId>
          <CategoryName>ansul</CategoryName>
         </Category>
         <Category>
          <CategoryId>3</CategoryId>
          <CategoryName>satish</CategoryName>
         </Category>
         <Category>
          <CategoryId>4</CategoryId>
          <CategoryName>tipu</CategoryName>
         </Category>
     </Categories>

My c# code is following for deleting a row from DataGridView and xml file. But my code always delete first row if I select any row from DataGridView and press the delete button.

 private void btnDelete_Click(object sender, EventArgs e)
     {           
        XmlDocument xdoc = new XmlDocument();
        string PATH = "xmldata.xml";

        ds.Clear();
        dtgvCategory.Refresh();
        ds.ReadXml(PATH);
        row = ds.Tables[0].Rows[0];
        int selectedRow = dtgvCategory.SelectedRows.Count;
        if (selectedRow > 0)
        {
            row.Delete();
        }

        ds.WriteXml(PATH);
        ds.AcceptChanges();
    }

I want code that delete only one selected row on button click event

Answer 1

Your current code always select row at index 0 as row , that's why it always delete the first row in the DataGridView.

You want to get row index of currently selected cell instead and you can try to get it from CurrentCell.RowIndex property. At this point you'll be able to delete row at that index :

int selectedRow = dtgvCategory.SelectedRows.Count;
if (selectedRow > 0)
{
    selectedRowIndex = dtgvCategory.CurrentCell.RowIndex;
    row = ds.Tables[0].Rows[selectedRowIndex];
    row.Delete();
}

Answer 2

you could add an eventhandler for when the row is selected using RowStateChanged:

public int SelectedRow = 0;

private void dtgvCategory_RowStateChanged(object sender, DataGridViewRowStateChangedEventArgs e)
    {
        // return if not StateChanged
        if (e.StateChanged != DataGridViewElementStates.Selected) return;

        // then you could put that row in a public variable
        SelectedRow = e.Row.Index;
    }

Now in your delete handler you know which row to delete.

https://msdn.microsoft.com/en-us/library/system.windows.forms.datagridviewrowstatechangedeventargs%28v=vs.110%29.aspx