public SubExpression[] GetSubExpressions()
{
if (string.IsNullOrWhiteSpace(ExpressionString))
{
return(null);
}
if (!ExpressionString.Contains('(') && !ExpressionString.Contains(')'))
{
return(GetSubs());
}
var subs = 0;
var currentExpression = string.Empty;
var result = new List <SubExpression>();
for (var i = 0; i < ExpressionString.Length; i++)
{
var c = ExpressionString[i];
if (c == '(')
{
subs++;
if (subs == 1)
{
if (!string.IsNullOrWhiteSpace(currentExpression))
{
result.Add(new SubExpression(currentExpression, this));
}
currentExpression = string.Empty;
}
else
{
currentExpression += c;
}
}
else if (c == ')')
{
subs--;
if (subs == 0)
{
if (!string.IsNullOrWhiteSpace(currentExpression))
{
result.Add(new SubExpression(currentExpression, this));
}
currentExpression = string.Empty;
}
else
{
currentExpression += c;
}
}
else if (ExpressionValues.IsMathSymbol(c) && subs == 0)
{
if (!string.IsNullOrWhiteSpace(currentExpression))
{
result.Add(new SubExpression(currentExpression, this));
}
currentExpression = string.Empty;
result.Add(new SubExpression(c.ToString(), this));
}
else
{
currentExpression += c;
}
}
if (!string.IsNullOrWhiteSpace(currentExpression))
{
result.Add(new SubExpression(currentExpression, this));
}
if (result.Count == 1 && result[0].ExpressionString == ExpressionString)
{
return(null);
}
//var newExpressions = new List<(int, SubExpression)>();
//for (var i = 0; i < result.Count; i++)
//{
// var se = result[i];
// if (se.ExpressionString.Length > 1)
// {
// if (se.ExpressionString.HasMathSymbol(0))
// {
// newExpressions.Add((i, new SubExpression(se.ExpressionString[0].ToString(), this)));
// se.ExpressionString = se.ExpressionString.Substring(1);
// }
// if (se.ExpressionString.HasMathSymbol(se.ExpressionString.Length - 1))
// {
// newExpressions.Add((i+1, new SubExpression(ExpressionString[se.ExpressionString.Length - 1].ToString(), this)));
// se.ExpressionString = se.ExpressionString.Substring(0, se.ExpressionString.Length - 1);
// }
// }
//}
//var offset = 0;
//foreach (var t in newExpressions)
//{
// result.Insert(t.Item1+offset++, t.Item2);
//}
return(result.ToArray());
}