Question

I want to create a string object like this

string data = "85-null-null-null-null-price-down-1-20";   // null if zero

I have a method like this.

 public static DataSet LoadProducts(int CategoryId, string Size, 
                                   string Colour, Decimal LowerPrice, 
                                   Decimal HigherPrice, string SortExpression, 
                                   int PageNumber, int PageSize, 
                                   Boolean OnlyClearance)
 {
      /// Code goes here 
      /// i am goona pass that string to one more method here

      var result = ProductDataSource.Load(stringtoPass) // which accepts only the above format

 }

I know I can use a StringBuilder, but using that would require too many lines of code. I am looking here for a minimalistic solution here.

Answer 1

You can do something like this:

return string.Format("{0}-{1}-{2}-{3}-{4}-{5}-{6}-{7}-{8}",
                     CategoryId,
                     Size ?? "null", 
                     Colour ?? "null",
                     LowerPrice != 0 ? LowerPrice.ToString() : "null",
                     HigherPrice != 0 ? HigherPrice.ToString() : "null",
                     SortExpression ?? "null",
                     PageNumber != 0 ? PageNumber.ToString() : "null",
                     PageSize != 0 ? PageSize.ToString() : "null", 
                     OnlyClearance);

For convenience, you could create extension methods:

public static string NullStringIfZero(this int value)
{
    return value != 0 ? value.ToString() : "null";
}

public static string NullStringIfZero(this decimal value)
{
    return value != 0 ? value.ToString() : "null";
}

And use them as follows:

return string.Format("{0}-{1}-{2}-{3}-{4}-{5}-{6}-{7}-{8}",
                     CategoryId,
                     Size ?? "null", 
                     Colour ?? "null",
                     LowerPrice.NullStringIfZero(),
                     HigherPrice.NullStringIfZero(),
                     SortExpression ?? "null",
                     PageNumber.NullStringIfZero(),
                     PageSize.NullStringIfZero(),
                     OnlyClearance);