Extract nested fields in Visual Studio Web load test

Question

Here is an html code I would like to test load and extract data from

<body>
    <h1>Hello StackOverflow</h1>

    <input type="hidden" name="Secret" value="66"/>
    <input type="hidden" name="Field[66].value" value="333" />
</body>

I need the 333 value. To do that, I need to extract the value 66 from Secret, and then use this value to deduce the name of the field (here Field[66].value). How can I do that?

I've tried to use two Extract Attribute Value extraction rules, but because there are on the same response, the first value is not yet in the context.

Why the downvote? It may be useful to explain why. – Matthieu Charbonnier Jan 10 '18 at 12:57 — Matthieu Charbonnier, Jan 10 '18 at 12:57

score 0 · Accepted Answer · answered Jan 10 '18 at 14:39

The solution was to create a Custom Extraction Rule as explained here and to use a regex to parse twice the html body

Extract Method:

public override void Extract(object sender, ExtractionEventArgs e)
{
    var val1 = GetInputValueByName(e.Response.BodyString, "Secret");
    var val2 = GetInputValueByName(e.Response.BodyString, $"Field[{val1}].value");

    if (!string.IsNullOrEmpty(val2 ))
    {
        e.Success = true;
        e.WebTest.Context.Add(this.ContextParameterName, val2);
    }
    else
    {
        // If the extraction fails, set the error text that the user sees
        e.Success = false;
        e.Message = String.Format(CultureInfo.CurrentCulture, "Not Found: {0}", Name);
    }

}


private string GetInputValueByName(string html, string name)
{
    Match match = Regex.Match(html, "<input[^>]*name=\"" + Regex.Escape(name) + "\"[^>]*value=\"([^\"]*)\"");
    if (match.Success)
    {
        return match.Groups[1].Value;
    }
    return string.Empty;
}

Extract nested fields in Visual Studio Web load test

1 Answers1