SampleApp.MainForm.GetCoordinateValue C# (CSharp) Method

        private void GetCoordinateValue(TextBox textBox)
        {
            int tag = int.Parse((string)textBox.Tag);
            int pointIndex = tag / 10;
            int coordinateIndex = tag % 10;
            float coordinateValue, oldValue = 0;

            textBox.Text = textBox.Text.Trim();

            // try parsing the coordinate value
            if (float.TryParse(textBox.Text, NumberStyles.Float, CultureInfo.InvariantCulture, out coordinateValue))
            {
                switch (coordinateIndex)
                {
                    case 0:
                        oldValue = modelPoints[pointIndex].X;
                        modelPoints[pointIndex].X = coordinateValue;
                        break;
                    case 1:
                        oldValue = modelPoints[pointIndex].Y;
                        modelPoints[pointIndex].Y = coordinateValue;
                        break;
                    case 2:
                        oldValue = modelPoints[pointIndex].Z;
                        modelPoints[pointIndex].Z = coordinateValue;
                        break;
                }
                errorProvider.Clear();

                if (oldValue != coordinateValue)
                {
                    ClearEstimation();
                }
            }
            else
            {
                Label pointLabel = (Label)modelPointsGroupBox.Controls[string.Format("modelPoint{0}Label", pointIndex + 1)];

                errorProvider.SetError(pointLabel, string.Format("Failed parsing {0} coordinate",
                    (coordinateIndex == 0) ? "X" : ((coordinateIndex == 1) ? "Y" : "Z")));

                textBox.Text = string.Empty;
            }
        }