Genericize access to variables
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I googled this extensively yesterday and didn't come out with an answer: Is it possible to do some thing like this, and if so how? labela1.Text = "something"; labela2.Text = "something"; labela3.Text = "something"; Now what I want is a way to write that code as say: for (int i=1;i<4;i++) labelai.Text = "something"; so that the i in labelai above is replaced by 1, 2, 3 at runtime and the net result of the for loop is the same as what happens in the block above. Is there a way to do that? Thanks!
Try to use this construction:
this.GetType().GetField("variablename")
This should work for c# but better try to avoid such kind of code. Other languages has different RTTI, for example in c/c++ this is impossible at all.
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I googled this extensively yesterday and didn't come out with an answer: Is it possible to do some thing like this, and if so how? labela1.Text = "something"; labela2.Text = "something"; labela3.Text = "something"; Now what I want is a way to write that code as say: for (int i=1;i<4;i++) labelai.Text = "something"; so that the i in labelai above is replaced by 1, 2, 3 at runtime and the net result of the for loop is the same as what happens in the block above. Is there a way to do that? Thanks!
Not sure about the performance implications of FindControl.. But this one is pretty close to what you originally wrote
for (int i=1;i<4;i++)
(Controls.FindControl("labela" + i.ToString()) as Label).Text = "something"; -
No-one with a LINQ version yet?
class Form1
{
IEnumerable<Control> summingLabels;public Form1() { InitializeComponent(); summingLabels = from c in Controls.Cast().AsQueryable() where c.Name.StartsWith("sumLabel") select c; // later on, when you need them foreach(Control l in summingLabels) l.Text = l.Name; }}
Keep a pointer around to the controls that you found; no need to iterate them every time :)
I are Troll :suss:
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I googled this extensively yesterday and didn't come out with an answer: Is it possible to do some thing like this, and if so how? labela1.Text = "something"; labela2.Text = "something"; labela3.Text = "something"; Now what I want is a way to write that code as say: for (int i=1;i<4;i++) labelai.Text = "something"; so that the i in labelai above is replaced by 1, 2, 3 at runtime and the net result of the for loop is the same as what happens in the block above. Is there a way to do that? Thanks!
This is not exactly what you were asking for but is an alternative using binding. This may be overkill for what you are trying to do but it would be more elegant. Bind your labels as you create them to an object of a class that implements INotifyChanged then when you change the property of the object each label will be updated without having to work loops. http://stackoverflow.com/questions/639894[^] Dave
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I googled this extensively yesterday and didn't come out with an answer: Is it possible to do some thing like this, and if so how? labela1.Text = "something"; labela2.Text = "something"; labela3.Text = "something"; Now what I want is a way to write that code as say: for (int i=1;i<4;i++) labelai.Text = "something"; so that the i in labelai above is replaced by 1, 2, 3 at runtime and the net result of the for loop is the same as what happens in the block above. Is there a way to do that? Thanks!
Array.ForEach(new Control[] { labela1, labela2, labela3 }, delegate(Control c) { c.Text = "something"; });
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how about lambda? :)
foreach (Control l in Controls.Cast().Where(c => c.Name.StartsWith("sumLabel")))
l.Text = l.Name;Lambda's look cool :cool: It's either searching through the collection and keeping the result around, or hardcoding them in advance. Attributes that mark a set of fields as a group might be another option, but that would add a bit more complexity. No, I think I like the lambda better. Would also be cool combined with a regex :) Nearly forgot, but that cast in my original query would be redundant, as we'd only need to store labels;
class Form1
{
IEnumerable summingLabels;
public Form1()
{
InitializeComponent();summingLabels = from c in Controls.Cast().AsQueryable() where c.GetType() == typeof(Label) && c.Name.StartsWith("label") select c as Label; // later on, when you need them foreach(Label l in summingLabels) l.Text = l.Location.ToString(); }}
I are Troll :suss:
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Lambda's look cool :cool: It's either searching through the collection and keeping the result around, or hardcoding them in advance. Attributes that mark a set of fields as a group might be another option, but that would add a bit more complexity. No, I think I like the lambda better. Would also be cool combined with a regex :) Nearly forgot, but that cast in my original query would be redundant, as we'd only need to store labels;
class Form1
{
IEnumerable summingLabels;
public Form1()
{
InitializeComponent();summingLabels = from c in Controls.Cast().AsQueryable() where c.GetType() == typeof(Label) && c.Name.StartsWith("label") select c as Label; // later on, when you need them foreach(Label l in summingLabels) l.Text = l.Location.ToString(); }}
I are Troll :suss:
Or Maybe to make it nicer with no casting and type checking:
summingLabels =
from c in Controls.OfType()
where c.Name.StartsWith("label")
select c;// later on, when you need them foreach(Label l in summingLabels) l.Text = l.Location.ToString(); -
Or Maybe to make it nicer with no casting and type checking:
summingLabels =
from c in Controls.OfType()
where c.Name.StartsWith("label")
select c;// later on, when you need them foreach(Label l in summingLabels) l.Text = l.Location.ToString(); -
I googled this extensively yesterday and didn't come out with an answer: Is it possible to do some thing like this, and if so how? labela1.Text = "something"; labela2.Text = "something"; labela3.Text = "something"; Now what I want is a way to write that code as say: for (int i=1;i<4;i++) labelai.Text = "something"; so that the i in labelai above is replaced by 1, 2, 3 at runtime and the net result of the for loop is the same as what happens in the block above. Is there a way to do that? Thanks!
How to do this is quite simple, but not obvious since we do not normally think of dimensioning a variable as a control type. The simplest way (to me) is to dimension an array of labels, Label(1), Label(2) etc. as Label. Then set each member of the array equal to each of the labels you want to control a property for. Then you can write a loop setting a property of each label in the array as an iterated function, such as: Dim Label(1) as Label Dim Label(2) as Label ... Label(1) = LabelA Label(2) = LabelB ... For x = 1 to 5 Label(x).text = "Text " & x Next (Sorry, I am an old VB.NET programmer, but the concept is the same in all :-D ) I think this is what you want, works great for me, and works for the other common controls, too.
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I googled this extensively yesterday and didn't come out with an answer: Is it possible to do some thing like this, and if so how? labela1.Text = "something"; labela2.Text = "something"; labela3.Text = "something"; Now what I want is a way to write that code as say: for (int i=1;i<4;i++) labelai.Text = "something"; so that the i in labelai above is replaced by 1, 2, 3 at runtime and the net result of the for loop is the same as what happens in the block above. Is there a way to do that? Thanks!
take a look at the dictionary class