/// <summary>
/// evalue the cell.
/// </summary>
/// <param name="input">input location.</param>
/// <returns>the value.</returns>
public override string Evaluate(string input)
{
ExpressionTree exp = new ExpressionTree(input);
string pattern = @"[A-Z](?:50|[1-4][0-9]|[1-9])";
SpreadsheetCell target;
foreach (Match m in Regex.Matches(input, pattern))
{
try
{
target = this.parentSpreadsheet.GetCell(m.Value);
exp.SetVariable(m.Value, Convert.ToDouble(target.Value));
target.PropertyChanged += (sender, e) => this.NotifyPropertyChanged(nameof(this.Value));
target.PropertyChanged += this.RefrencePropertyChanged;
}
catch
{
return("!CellNotDefined");
}
}
return(exp.Evaluate().ToString());
}
/// <summary>
/// envent to change cell.
/// </summary>
/// <param name="sender">sender.</param>
/// <param name="e">e.</param>
private void CellPropertyChanges(object sender, PropertyChangedEventArgs e)
{
SpreadsheetCell spreadsheet = sender as SpreadsheetCell;
Dictionary <int, char> alp = new Dictionary <int, char>();
int count = 0;
for (char i = 'A'; i <= 'Z'; i++)
{
alp[count] = i;
count++;
}
string changeCell = alp[spreadsheet.ColumIndex].ToString() + (spreadsheet.RowIndex + 1).ToString();
if (e.PropertyName == "Text")
{
if (spreadsheet.Text.StartsWith("=") == false)
{
spreadsheet.Value = spreadsheet.Text;
}
else
{
// if equal to the expreesion which need to cal by expression tree.
if (spreadsheet.Text.Length > 3)
{
string expression = spreadsheet.Text.Substring(1);
ExpressionTree tree = new ExpressionTree(expression);
List <string> strlist = tree.GetVaribles(expression);
foreach (string var in strlist)
{
SpreadsheetCell cell = this.GetSingleValue(var);
if (cell != null)
{
if (this.GetSingleValue(changeCell) == this.GetSingleValue(var))
{
spreadsheet.Value = "!self reference";
}
else if (this.GetSingleValue(var).Value != "!self reference")
{
double value = Convert.ToDouble(this.GetSingleValue(var).Value);
tree.SetVariable(var, value);
spreadsheet.Value = tree.Evaluate().ToString();
}
else
{
spreadsheet.Value = Convert.ToString(0);
}
cell.PropertyChanged += spreadsheet.CellPropertyChanged;
}
else
{
spreadsheet.Value = "!bad reference";
}
}
}
// if = like B1,A1 just single cell value.
else
{
string name = spreadsheet.Text.Substring(1);
SpreadsheetCell cell = this.GetSingleValue(name);
// cell will be null if catch FormatException case which return to null,if not, just normall to get value else will be bad reference.
if (cell != null)
{
// if equal self cell value
if (this.GetSingleValue(changeCell) == this.GetSingleValue(name))
{
spreadsheet.Value = "!self reference";
}
// if equal the cell value which is no self reference, else is equal zero.
else if (this.GetSingleValue(name).Value != "!self reference")
{
spreadsheet.Value = this.GetSingleValue(name).Value;
}
else
{
spreadsheet.Value = Convert.ToString(0);
}
cell.PropertyChanged += spreadsheet.CellPropertyChanged;
}
else
{
spreadsheet.Value = "!bad reference";
}
}
}
}
this.CellPropertyChanged?.Invoke(sender, new PropertyChangedEventArgs("Value"));
}