Question

I have converted my Datatable to json string use the following method…

public string GetJSONString(DataTable Dt)
{
    string[] StrDc = new string[Dt.Columns.Count];
    string HeadStr = string.Empty;
    for (int i = 0; i < Dt.Columns.Count; i++)
    {
        StrDc[i] = Dt.Columns[i].Caption;
        HeadStr += "\"" + StrDc[i] + "\" : \"" + StrDc[i] + i.ToString() + "¾" + "\",";
    }
    HeadStr = HeadStr.Substring(0, HeadStr.Length - 1);
    StringBuilder Sb = new StringBuilder();

    Sb.Append("{\"" + Dt.TableName + "\" : [");
    for (int i = 0; i < Dt.Rows.Count; i++)
    {
        string TempStr = HeadStr;
        Sb.Append("{");
        for (int j = 0; j < Dt.Columns.Count; j++)
        {
            if (Dt.Rows[i][j].ToString().Contains("'") == true)
            {
                Dt.Rows[i][j] = Dt.Rows[i][j].ToString().Replace("'", "");
            }
            TempStr = TempStr.Replace(Dt.Columns[j] + j.ToString() + "¾", Dt.Rows[i][j].ToString());
        }
        Sb.Append(TempStr + "},");
    }
    Sb = new StringBuilder(Sb.ToString().Substring(0, Sb.ToString().Length - 1));
    Sb.Append("]}");
    return Sb.ToString();
}

Is this fair enough or still there is margin for optimization to make it execute faster…. Any suggestion…

Answer 1

Before asking if you can optimise it to make it execute faster, the first question you need to ask yourself is, does it run fast enough for me? Premature optimisation is the curse of all of us (I know I’ve done it!). You could spend hours trying to micro-optimise this code, which might take it from taking, for example, 20ms to execute down to 15ms. Yes that’d be a reduction of 25%, but would 5ms really be worth 2 hours of your time? More importantly, would it provide enough of a benefit to your end users to warrant it?

Have you considered using the JsonSerializer from “Newtonsoft”? This may well be “quick enough”, is fairly widely used and is thus more likely to be correct overall than anything I, or you, can write first time round.

Purely from a readability perspective (that may also allow the C# compiler / CLR to improve thing for you) you could consider changing long bits of string concatenation such as:

HeadStr += "\"" + StrDc[i] + "\" : \"" + StrDc[i] + i.ToString() + "¾" + "\",";

To:

HeadStr += string.Format("\"{0}\" : \"{0}{1}¾\",", strDc[i], i);

But for any changes you do make. Measure, Rinse, Repeat =)