Iterate over object fields in C#
Foo
is a class with a lot of string fields. I want to create a method Wizardify
that performs an operation on many of the fields of the object. I could do it like this:
Foo Wizardify(Foo input)
{
Foo result;
result.field1 = Bar(input.field1);
result.field2 = Bar(input.field2);
result.field3 = Bar(input.field3);
...
This is some easily generated cod开发者_StackOverflow社区e, but I prefer not to waste fifty lines on this. Is there a way to go over selected fields of an object? Note that there are four or five fields I want to work on in a different way and they should be excluded from the iteration.
try
foreach ( FieldInfo FI in input.GetType().GetFields () )
{
FI.GetValue (input)
FI.SetValue (input, someValue)
}
Though I would not recommend the reflection approach for known Types - it is slow and depending on your specific scenario could pose some permission issue at runtime...
This is what I have - it gives me a list (names) of all properties in my classes, that later I can work on with Reflection or "Expression trees":
private static string xPrev = "";
private static List<string> result;
private static List<string> GetContentPropertiesInternal(Type t)
{
System.Reflection.PropertyInfo[] pi = t.GetProperties();
foreach (System.Reflection.PropertyInfo p in pi)
{
string propertyName = string.Join(".", new string[] { xPrev, p.Name });
if (!propertyName.Contains("Parent"))
{
Type propertyType = p.PropertyType;
if (!propertyType.ToString().StartsWith("MyCms"))
{
result.Add(string.Join(".", new string[] { xPrev, p.Name }).TrimStart(new char[] { '.' }));
}
else
{
xPrev = string.Join(".", new string[] { xPrev, p.Name });
GetContentPropertiesInternal(propertyType);
}
}
}
xPrev = "";
return result;
}
public static List<string> GetContentProperties(object o)
{
result = new List<string>();
xPrev = "";
result = GetContentPropertiesInternal(o.GetType());
return result;
}
Usage: List<string> myProperties = GetContentProperties(myObject)
;
Loop through typeof(YourType).GetProperties()
and call GetValue
or SetValue
.
Note that reflection is rather slow.
You could use the Dynamic Language Runtime to generate a lambda of the type Func. You'll just need to generate the lambda once (you can cache it away) and there'll be no reflection performance hit.
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