How to perform this task?
int Amount, x=1000,y=200;
string BasedOn="x*12/100+y*5/100";
//In place of x and y in BasedOn I want to replace with x,y values like (1000*12%+200*5%)
//and the calculated result(130) should be assigned to Amount variable
For now, I split the BasedOn string
string[][] strings = BasedOn
.Split(new char[] { '+' }, StringSplitOptions.RemoveEmptyEntries)
.Select(w => w.Split('*').ToArray())
.ToArray();
What to do next? Please help me.
I made your code more flexible
static void Main(string[] args)
{
Dictionary<string, object> variables = new Dictionary<string, object>();
variables.Add("x", 1000);
variables.Add("y", 200);
string equation = "x*12/100+y*5/100";
var result = Calculate(variables, equation);
}
static object Calculate(Dictionary<string, object> variables, string equation)
{
variables.ToList().ForEach(v => equation = equation.Replace(v.Key, v.Value.ToString()));
return new DataTable().Compute(equation, string.Empty);
}
You can take a look on the DataTable.Compute method. It can be used like this on your case:
using System.Data;
DataTable dt = new DataTable();
var Amount = dt.Compute("1000*12%+200*5%","");
For replacing "x" and "y" with numeric values you can use string.Replace
Take a look NCalc (http://ncalc.codeplex.com/)
Expression e = new Expression("2 + 3 * 5");
Debug.Assert(17 == e.Evaluate());
If you want to replace the string AND calculate the result, you can do:
int Amount, x=1000,y=200;
string BasedOn=$"{x}*12/100+{y}*5/100";
DataTable dt = new DataTable();
var v = dt.Compute(BasedOn,"");
v will be your result (130).
EDIT: You have to replace your %'s with division by 100, as the datatable thinks its a mod operator.
string.Empty instead of double quotes ("")?With DataColumn.Expression:
int Amount, x = 1000, y = 200; string BasedOn = "x*12%+y*5%";
var dt = new DataTable();
dt.Columns.Add("x", typeof(int)); // in Visual Studio 2015 you can use nameof(x) instead of "x"
dt.Columns.Add("y", typeof(int));
dt.Columns.Add("Amount", typeof(int), BasedOn.Replace("%", "/100")); // "x*12/100+y*5/100" ("%" is considered modulus operator)
Amount = (int)dt.Rows.Add(x, y)["Amount"]; // 130
With RegEx.Replace and DataTable.Compute:
string expression = Regex.Replace(BasedOn.Replace("%", "/100"), "[a-zA-Z]+",
m => (m.Value == "x") ? x + "" : (m.Value == "y") ? y + "" : m.Value); // "1000*12/100+200*5/100"
Amount = (int)(double)new DataTable().Compute(expression, ""); // 130.0 (double)
