linq to sql only selecting data from columns in object that are not null
i am trying to build up a string containing the values of fields in a linq to sql object. the thing is, i only want to grab the fields that are not null
i am sure there is a way to do this. can anyone enlighten me?
mylinqdatacontext dc = new mylinqdatacontext;
StringBuilder sb = new 开发者_如何学JAVAStringBuilder();
mylinqtype item = (from x in dc.mylinqtypes where x.id.equals(1)).single();
var props = typeof(mylinqtype).GetProperties();
foreach(PropertyInfo p in props){
if(item... != null){
sb.append(p.name + " :" + item[p].value; //or some such i dont really know
}
}
any help much appreciated
i have tried
object theValue = p.getgetmethod().invoke(item, null);
but it threw a System.Reflection.TargetException thanks
nat
This is untested, but I think it should get you close at least:
SomeDataContext dc = new SomeDataContext();
StringBuilder sb = new StringBuilder();
SomeItem item = (from x in dc.SomeItems where x.SomeItemId == 1 select x).Single();
PropertyInfo[] props = item.GetType().GetProperties();
foreach (PropertyInfo p in props)
{
if (p.CanRead) // might need more tests here for various attributes of the property
{
object val = p.GetValue(item, null);
if (val != null)
{
sb.Append(p.Name + " : " + val);
}
}
}
using (var dc = new DataContext())
{
var result = dc.Entities.Where(x => c.Column != null).Select(x => x.Column)
.Aggregate((x, y) => x + y);
}
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