clearscreen()

clearscreen()

• RazzleDazzle

  Thank you, Cathal,
  
  In creating my own clearscreen ()
  I should code something like this on my winform
  
  sub clearscreen(passedContainer as control)
  Dim ctl as control
  
  ' This clears the textbox txtName
  If CType(ctl, txtName).Text = " "
  
  End If
  
  ' This clears the label lblResults
  If CType(ctl, lblResults).Text = " "
  
  End If
  

• Mujeeb_rahman

  sorry i never made it clear that the previous solution was applicable for webforms, for winforms similar code works, you just reference passedContainer.Controls
  
  Cathal
  

• Alin Constantin - MSFT

  theres lots of options, depending on how reusable you want the code to be.The simplest is just to create a sub that names the individual controls you want cleared e.g
  sub clearAll
  txtCalc.text=""
  lblCalcResults.text=""
  end sub
  
  Alternatively, you can use a naming scheme to determine what controls to clear e.g using a variation on the earlier code, you add an additional check, and only clear labels that being with some predetermined string i.e. in this example labels called lblClrResult and lblClrResult2 would be cleared, but a label called lblDontTouch would be ignored.
  
  dim ctl as control
  if typeof ctl is label then
     if ctl.name.StartsWith("lblClr") then
        ctype(ctl, label).text=""
     end if
  end if
  ...any other types as well e.g.
  end sub
  
  Another scheme some people use is to initially set values on both the tag and text properties, and then check if they differ when a clear button is set and reset them to their initial values. This means non-editable values are never cleared e.g.
  
  txtResult.tag="Please enter some text"
  txtResult.text="Please enter some text"
  
  and when someone clicks the clear button you do:
  if txtResult.text<>txtResult.tag then
  txtResult.text=txtResult.tag
  end if
  
  Obviously you can combine this with the earlier control looping i.e.
  if typeof ctl is textbox then
     if ctype(ctl, textbox).text<>ctype(ctl, textbox).tag then
        ctype(ctl, textbox).text=ctype(ctl, textbox).tag
     end if
  end if
  
  Cathal
  

• Hamish_NZ

  Hello Daniel,
  
  please understand, I am not a programmer and have a great deal of difficulty getting these things straight in my head. This is all a learning experience and I am grateful for assistance, guidance and straight code help. 
  
  Thank you for the note,  I honestly did not think about how .net might handle something like that. I have been in class for 2 weeks so I am learning.
  
  best regards,
  Gary
  

• SAS8721

  Hello Cathal,
  
  I used the Case Label which cleared the label however, it also clears the labels of the text boxes. I need to restore those labels
  
  can I declare a Temp for each of the text I need to restore and code to replace the labels I did not want cleared or is there an easy way to clear specific labels   ie  only the labels that contain results of computations performed in the code. Originally, these labels have no text value they get their text from code.
  

• Scafe

  You can code your own, something like this should do it. Pass in the container control i.e. the form/groupbox etc. clearScreen(grpEdit)
  

  sub clearScreen(passedContainer as control) Dim ctl As Control   For Each ctl In passedContainer.Controls(1).Controls   If TypeOf ctl Is TextBox Then   CType(ctl, TextBox).Text = ""   End If If TypeOf ctl Is LabelThen   CType(ctl, Label).Text = ""   End If Next

  
  
  Cathal
  

• Michela

  I don't ClearScreen is a built-in method. How should .NET know which textboxes you want to clear, or whether it should clear the text or set it to some default value
  
  You will need to create your own method to do that.
  
  

• yimin chen

  Good Morning Cathal,
  
  well, I had it close and with your guidance, it works.  I think I am learning but programming is not what I really do.  I love the hardware part of my job, I need to understand more about programming but will not, I am sure, ever get into programming.  thank you for your help, I will have many more questions as this class runs through Christmas. This forum is wonderful and everyone I have met so far is very gererous. I am appreciative! 
  
  best regards,
  Gary
  

• Arul Ram

  chipscap wrote:

  Thank you, Cathal, In creating my own clearscreen () I should code something like this on my winform sub clearscreen(passedContainer as control) Dim ctl as control ' This clears the textbox txtName If CType(ctl, txtName).Text = " " End If ' This clears the label lblResults If CType(ctl, lblResults).Text = " " End If

  
  No, you don't need to reference your field, we're referencing them by their type,which means it's generic i.e. it will do every textbox is a container (containers such as panels, groupboxs, forms etc.) (sorry the " " is a typo, theres no space). In fact a good way to do this, is to create a shared function in a helper class eg.
  
  Public Class MyHelperMethods
  
  public Shared Sub(byref passedContainer as control)
  dim ctl as control
  if typeof ctl is textbox then
  ctype(ctl, textbox).text=""
  end if
  ...any other types as well e.g.
  end sub
  end class
  
  Cathal
  
  
• clearscreen()