Search list of objects based on object variable
I have a list of objects. These objects have three variables, ID, Name, & value. Th开发者_JAVA技巧ere can be a lot of objects in this list, and I need to find one based on the ID or Name, and change the value. Example
class objec
{
public string Name;
public int UID;
public string value;
}
List<objec> TextPool = new List<objec>();
How would I find the one entry in TextPool that had the Name of 'test' and change its value to 'Value'. The real program has many more search options, and values that need changing, so I couldn't just use a Dictionary (though Name and UID or unique identifiers). Any help would be great
You could use LINQ to find it, then change the element directly:
var item = TextPool.FirstOrDefault(o => o.Name == "test");
if (item != null)
item.value = "Value";
If you wanted to change all elements that match, you could, potentially, even do:
TextPool.Where(o => o.Name == "test").ToList().ForEach(o => o.value = "Value");
However, I personally would rather split it up, as I feel the second option is less maintainable (doing operations which cause side effects directly on the query result "smells" to me)...
var find = TextPool.FirstOrDefault(x => x.Name == "test");
if (find != null)
{
find.Name = "Value";
}
Sounds like a job for LINQ!
var matchedObject =
from t in TextPool
where t.UName == "test"
select t;
This is assuming your search is defined in code. If your code is driven by the UI, you may simply need to do a linear iteration. To search all possible attributes, without indexing, it isn't going to get any faster.
[ Edit: Was beaten to the punch, but leaving this up as an example of a different syntax, plus a link ]
List<objec> TextPool = new List<objec>();
objec found = TextPool.FirstOrDefault(item => item.Name == "test");
if (found != null) found.value = "Value";
If you are going to perform many lookups, you could cache the results in multiple Dictionary<> instances (or Lookup<> instance if keys are not unique).
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