How to generate XML by reading value from collection using XDocument?

Question

I have a list of string

List<string> lststr = new List<string>() { "1,", "2" };

I need to generate the below

<DbRuleMappings>
  <DbRuleMapping dbDetailId="1" ruleMasterId="1" activeFlag="1" />
  <DbRuleMapping dbDetailId="1" ruleMasterId="2" activeFlag="1" />
  <DbRuleMapping dbDetailId="1" ruleMasterId="3" activeFlag="1" />
  <DbRuleMapping dbDetailId="1" ruleMasterId="4" activeFlag="1" />
  <DbRuleMapping dbDetailId = "2" ruleMasterId="1" activeFlag="1"/>
  <DbRuleMapping dbDetailId = "2" ruleMasterId="2" activeFlag="1"/>
  <DbRuleMapping dbDetailId = "2" ruleMasterId="3" activeFlag="1"/>
  <DbRuleMapping dbDetailId = "2" ruleMasterId="4" activeFlag="1"/>
 </DbRuleMappings>

My attempt ...not working

List<string> lststr = new List<string>() { "1,", "2" };            

XDocument docDBRuleMapping =
        new XDocument(
           new XElement("DbRuleMappings",
                   Enumerable.Range(1, 4).Select(x => x)
                   .Select(i => new XElement("DbRuleMapping",  
                           new XAttribute("dbDetailId", i),
                           new XAttribute("ruleMasterId", i),
                           new XAttribute("activeFlag", 1)))));

Answer 1

You're currently not using lststr at all. You need to basically use SelectMany to join lststr with your Enumerable.Range . That's probably done most easily with a query expression:

var detailIds = new List<int> { 1, 2 };

var doc = new XDocument(new XElement("DbRuleMappings",
    from detailId in detailIds
    from ruleId in Enumerable.Range(1, 4)
    select new XElement("DbRuleMapping",  
        new XAttribute("dbDetailId", detailId),
        new XAttribute("ruleMasterId", ruleId),
        new XAttribute("activeFlag", 1))));

(I've changed the input to be a List<int> rather than a List<string> given the data... it would work fine with a List<string> if you really need that though.

If you don't like query expressions, here's the equivalent without:

var detailIds = new List<int> { 1, 2 };

var doc = new XDocument(new XElement("DbRuleMappings",
    detailIds.SelectMany(_ => Enumerable.Range(1, 4),
        (detailId, ruleId) => new XElement("DbRuleMapping",  
            new XAttribute("dbDetailId", detailId),
            new XAttribute("ruleMasterId", ruleId),
            new XAttribute("activeFlag", 1)))));