DataGridView HasErrors?

Question

I wish to prevent the user from saving changes made to a DataGridView if it has any validation errors (set using the ErrorText property of a cell using the CellValidating event).

I'm looking for (but cannot see) a method such as myDataGridView.HasErrors()?

Answer 1

in msdn there is an example on how to validate the DataGridView have a look...

DataGridView

i hope it helped

Answer 2

Just do it at the same time you are validating the rows. Using the MSDN example arik posted...

private void dataGridView1_CellValidating(object sender,
    DataGridViewCellValidatingEventArgs e)
{
    dataGridView1.Rows[e.RowIndex].ErrorText = "";
    int newInteger;

    if (dataGridView1.Rows[e.RowIndex].IsNewRow) { return; }
    if (!int.TryParse(e.FormattedValue.ToString(),
        out newInteger) || newInteger < 0)
    {
        e.Cancel = true;
        dataGridView1.Rows[e.RowIndex].ErrorText = "the value must be a non-negative integer";

        //If it's simple, do something like this here.
        this.SubmitButton.Enabled = false;

        //If not, set a private boolean variable scoped to your class that you can use elsewhere.
        this.PassedValidation = false;
    }
}

Answer 3

I imagine that the issue has been solved now, but I'll add my solution to help others facing the same issue regarding coping with multiple-field validation:

I created some pubilc variables to store whetehr the input is valid or not:

public bool validation1_valid = true;
public bool validation2_valid = true;

Then, in the DataGrid's _CellValueChanged method:

private void gridView_CellValueChanged(object sender, DataGridViewCellEventArgs e)
    {
        string cellHeader = gridView.Columns[e.ColumnIndex].HeaderText.ToString();

       //if cell is one that needs validating
       if (cellHeader == "Something" || cellHeader == "Something Else")
       {
           //if it isn't null/empty
           if (gridView.Rows[e.RowIndex].Cells[e.ColumnIndex].Value != null
               && gridView.Rows[e.RowIndex].Cells[e.ColumnIndex].Value.ToString() != "")
           {
               //check if it's valid (here using REGEX to check if it's a number)                  
               if (System.Text.RegularExpressions.Regex.IsMatch(gridView.Rows[e.RowIndex].Cells[e.ColumnIndex].Value.ToString(), @"^(?:^\d+$|)$"))
               {
                   //set the relevant boolean if the value to true if the cell it passes validation
                   switch (cellHeader)
                   {
                       case "Something":
                           validation1_valid= true;
                           break;
                       case "Something Else":
                           validation2_valid= true;
                           break;
                   }

                   //Add an error text
                   gridView.Columns[e.ColumnIndex].DefaultCellStyle.ForeColor = Color.Black;
                   gridView.Rows[e.RowIndex].Cells[e.ColumnIndex].ErrorText = String.Empty;
                   gridView.Rows[e.RowIndex].ErrorText = String.Empty;

                   //DON'T disable the button here - it will get changed every time the validation is called
               }
               else //doesn't pass validation
               {
                   //set boolean to false
                   switch (cellHeader)
                   {
                       case "Something":
                           validation1_valid = false;
                           break;
                       case "Something Else":
                           validation2_valid = false;
                           break;
                   }

                   gridView.Columns[e.ColumnIndex].DefaultCellStyle.ForeColor = Color.Red;
                   gridView.Rows[e.RowIndex].Cells[e.ColumnIndex].ErrorText = "Value must be numeric.";
                }
           }
           else //null or empty - I'm allowing these, so set error to "" and booleans to true
           {
               switch (cellHeader)
                   {
                       case "Something":
                           validation1_valid = true;
                           break;
                       case "Something Else":
                           validation2_valid = true;
                           break;
                   }
               gridView.Columns[e.ColumnIndex].DefaultCellStyle.ForeColor = Color.Black;
               gridView.Rows[e.RowIndex].Cells[e.ColumnIndex].ErrorText = String.Empty;
               gridView.Rows[e.RowIndex].ErrorText = String.Empty;
           }
       }

       //if there is an invalid field somewhere
       if (validation1_valid == false || validation2_valid == false)
       {
           //set the button to false, and add an error to the row
           btnSave.Enabled = false;
           gridView.Rows[e.RowIndex].ErrorText = "There are validation errors.";
       }
       //else if they're all vaild
       else if (validation1_valid == true && validation2_valid == true)
       {
           //set the button to true, and remove the error from the row
           btnSave.Enabled = true;
           gridView.Rows[e.RowIndex].ErrorText = String.Empty;
       }
    }