sharepoint - 如何获取 SPFieldLookup 的所有可能值

Question

我在 sharepoint 中有一个查找字段，它只引用另一个列表。我想知道如何以编程方式枚举该字段的所有可能值？例如，我的查找字段“实际城市”指的是列表“城市”和列“标题”，那里有 3 个城市。在代码中，我想获取字段“实际城市”的所有可能值的列表，类似于(元代码，抱歉):


SPFieldLookup f = myList["Actual City"];<br/>
Collection availableValues = f.GetAllPossibleValues();<br/>
//this should return collection with all cities a user might select for the field


Answer 1

前几天我为我的项目编写了一些代码来处理这个问题。也许它会有所帮助。

    public static List<SPFieldLookupValue> GetLookupFieldValues(SPList list, string fieldName)
    {
        var results = new List<SPFieldLookupValue>();
        var field = list.Fields.GetField(fieldName);

        if (field.Type != SPFieldType.Lookup) throw new SPException(String.Format("The field {0} is not a lookup field.", fieldName));

        var lookupField = field as SPFieldLookup;
        var lookupList = list.ParentWeb.Lists[Guid.Parse(lookupField.LookupList)];
        var query = new SPQuery();

        query.Query = String.Format("<OrderBy><FieldRef Name='{0}'/></OrderBy>", lookupField.LookupField);

        foreach (SPListItem item in lookupList.GetItems(query))
        {
            results.Add(new SPFieldLookupValue(item.ID, item[lookupField.LookupField].ToString()));
        }

        return results;
    }

然后要使用它，您的代码将如下所示:

        var list = SPContext.Current.Web.Lists["My List"];
        var results = GetLookupFieldValues(list, "Actual City");

        foreach (SPFieldLookupValue result in results)
        {
            var value = result.LookupValue;
            var id = result.LookupId;
        }