Se acabaron las funciones recursivas para definir CAML Queries gracias a Camlex

Algunas veces tienes un número aleatorio de condiciones para incluir en una CAML query y en esos casos yo solía definir las consultas usando una función recursiva que normalmente tenía que debugar unas cuantas veces me funciona siempre a la primera.

El código para este tipo de consultas sería algo así (y este es de los simples):

view plainprint?

1. public List<string> GetSomeInfo(string fieldsToSearch, string contentTypesToSearch)  
2. {  
3.     ...  
4.   
5.     var queryval = string.Empty;  
6.     if (contentTypesToSearch.IsNullOrEmpty())  
7.         queryval = string.Format("<Where>" + GenerateFieldsQuery(fieldsToSearch.Split(','), 0) + "</Where>", text);  
8.     else  
9.         queryval = string.Format("<Where><And>" + GenerateCTypesQuery(contentTypesToSearch.Split(','), 0) + GenerateFieldsQuery(fieldsToSearch.Split(','), 0) + "</And></Where>", text);  
10.   
11.     var scope = "Scope=\"RecursiveAll\"";  
12.   
13.     ...  
14. }  
15.   
16. private static string GenerateFieldsQuery(string[] fields, int index)  
17. {  
18.     if (fields.Length == 0) return string.Empty;  
19.   
20.     if (fields.Length == index + 1)  
21.         return "<Contains><FieldRef Name='" + fields[index] + "' /><Value Type='Text'>{0}</Value></Contains>";  
22.   
23.     return "<Or><Contains><FieldRef Name='" + fields[index] + "' /><Value Type='Text'>{0}</Value></Contains>" + GenerateFieldsQuery(fields, ++index) + "</Or>";  
24. }  
25.   
26. private static string GenerateCTypesQuery(string[] cTypes, int index)  
27. {  
28.     if (cTypes.Length == 0) return string.Empty;  
29.   
30.     if (cTypes.Length == index + 1)  
31.         return "<Eq><FieldRef Name='ContentType' /><Value Type='Choice'>" + cTypes[index] + "</Value></Eq>";  
32.   
33.     return "<Or><Eq><FieldRef Name='ContentType' /><Value Type='Choice'>" + cTypes[index] + "</Value></Eq>" + GenerateCTypesQuery(cTypes, ++index) + "</Or>";  
34. }  

public List<string> GetSomeInfo(string fieldsToSearch, string contentTypesToSearch)
{
    ...

    var queryval = string.Empty;
    if (contentTypesToSearch.IsNullOrEmpty())
        queryval = string.Format("<Where>" + GenerateFieldsQuery(fieldsToSearch.Split(','), 0) + "</Where>", text);
    else
        queryval = string.Format("<Where><And>" + GenerateCTypesQuery(contentTypesToSearch.Split(','), 0) + GenerateFieldsQuery(fieldsToSearch.Split(','), 0) + "</And></Where>", text);

    var scope = "Scope=\"RecursiveAll\"";

    ...
}

private static string GenerateFieldsQuery(string[] fields, int index)
{
    if (fields.Length == 0) return string.Empty;

    if (fields.Length == index + 1)
        return "<Contains><FieldRef Name='" + fields[index] + "' /><Value Type='Text'>{0}</Value></Contains>";

    return "<Or><Contains><FieldRef Name='" + fields[index] + "' /><Value Type='Text'>{0}</Value></Contains>" + GenerateFieldsQuery(fields, ++index) + "</Or>";
}

private static string GenerateCTypesQuery(string[] cTypes, int index)
{
    if (cTypes.Length == 0) return string.Empty;

    if (cTypes.Length == index + 1)
        return "<Eq><FieldRef Name='ContentType' /><Value Type='Choice'>" + cTypes[index] + "</Value></Eq>";

    return "<Or><Eq><FieldRef Name='ContentType' /><Value Type='Choice'>" + cTypes[index] + "</Value></Eq>" + GenerateCTypesQuery(cTypes, ++index) + "</Or>";
}

Eso era hasta ahora... gracias a Camlex (y gracias a Luis por decírmelo), este código se puede escribir así:

view plainprint?

1. public List<string> GetSomeInfo(string fieldsToSearch, string contentTypesToSearch)  
2. {  
3.     ...  
4.   
5.     var queryVal = string.Empty;  
6.     var fieldExtensions = new List<Expression<Func<SPListItem, bool>>>();  
7.     var cTypeExtensions = new List<Expression<Func<SPListItem, bool>>>();  
8.   
9.     if (!contentTypesToSearch.IsNullOrEmpty())  
10.     {  
11.         foreach (var cType in contentTypesToSearch.Split(','))  
12.             cTypeExtensions.Add(x => (string)x["ContentType"] == cType);  
13.     }  
14.   
15.     foreach (var field in fieldsToSearch.Split(','))  
16.         fieldExtensions.Add(x => ((string)x[field]).Contains(text));  
17.   
18.     var expressions = new List<Expression<Func<SPListItem, bool>>>();  
19.     expressions.Add(ExpressionsHelper.CombineOr(cTypeExtensions));  
20.     expressions.Add(ExpressionsHelper.CombineOr(fieldExtensions));  
21.   
22.     queryVal = Camlex.Query().WhereAll(expressions).ToString();  
23.   
24.     ...  
25. }  

public List<string> GetSomeInfo(string fieldsToSearch, string contentTypesToSearch)
{
    ...

    var queryVal = string.Empty;
    var fieldExtensions = new List<Expression<Func<SPListItem, bool>>>();
    var cTypeExtensions = new List<Expression<Func<SPListItem, bool>>>();

    if (!contentTypesToSearch.IsNullOrEmpty())
    {
        foreach (var cType in contentTypesToSearch.Split(','))
            cTypeExtensions.Add(x => (string)x["ContentType"] == cType);
    }

    foreach (var field in fieldsToSearch.Split(','))
        fieldExtensions.Add(x => ((string)x[field]).Contains(text));

    var expressions = new List<Expression<Func<SPListItem, bool>>>();
    expressions.Add(ExpressionsHelper.CombineOr(cTypeExtensions));
    expressions.Add(ExpressionsHelper.CombineOr(fieldExtensions));

    queryVal = Camlex.Query().WhereAll(expressions).ToString();

    ...
}

Echaré de menos los métodos recursivos... me hacían sentir especial...