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POcustom textboxes in VB.Net
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copied!<p>tldr - Made a subclass of Textbox, text looks screwy when it has focus. What's the proper way to handle it?</p> <p>For my company's VB.Net application, I've been asked to make our textboxes behave like Google's textboxes, ie they need to have a blue-ish border around them when they have focus and a gray-ish border when they do not. I can already accomplish this by setting a textbox's BorderStyle to 'None', then drawing the appropriate rectangle within a form's Paint event. However, I have to do this for each and every single textbox that I use. And our application has quite a few of them. Needless to say, this is a pain and I'd rather have one piece of code that I can call upon.</p> <p>So I figured that I have two options; I can either make a user control that contains a single textbox which uses the above method, or I can write my own class that inherits from the TextBox class and makes this behavior standard. I have elected to use the latter approach, and via overriding the OnPaint method I have achieved the desired behavior. But now I'm encountering some new pitfalls.</p> <p>The main problem that I'm having is that text within the textbox is not rendered correctly when the textbox has focus. The text takes on a different font, appears bold, and highlighting looks wonky. If the textbox loses focus, the text looks correct. I suspect that I need to handle drawing for highlighted text differently, but I'm not sure what I need to do. Do I handle it in the OnPaint method or do I need to catch it somewhere else? Do I need to abandon this approach altogether and just make a user control?</p> <p>Bonus question: for anyone with experience making custom textboxes, are there any tips or gotchas that I need to know about? This is my first time making a custom control, so I don't really know what all to expect.</p> <p>edit: forgot to mention that I'm able to override OnPaint because I set the UserPaint flag to true. I'm guessing this was obvious, but I just want to be thorough.</p> <p>edit2: Here's the class in its entirety.</p> <pre><code>Imports System.Drawing Public Class MyCustomTextBox Inherits TextBox Public Sub New() MyBase.New() Me.BorderStyle = BorderStyle.None SetStyle(ControlStyles.UserPaint, True) End Sub Protected Overrides Sub OnGotFocus(ByVal e As System.EventArgs) 'I want these textboxes to highlight all text by default Me.SelectAll() MyBase.OnGotFocus(e) End Sub Protected Overrides Sub OnLostFocus(ByVal e As System.EventArgs) Me.SelectionLength = 0 MyBase.OnLostFocus(e) End Sub Protected Overrides Sub OnPaint(ByVal e As System.Windows.Forms.PaintEventArgs) Dim p As Pen = Nothing 'MyBase.OnPaint(e) e.Graphics.FillRectangle(Brushes.White, Me.ClientRectangle) If Me.Focused Then p = New Pen(Brushes.CornflowerBlue) Else p = New Pen(Brushes.Gainsboro) End If e.Graphics.DrawRectangle(p, 0, 0, Me.ClientSize.Width - 1, Me.ClientSize.Height - 1) e.Graphics.DrawString(Me.Text, Me.Font, New SolidBrush(Me.ForeColor), Me.ClientRectangle) End Sub End Class </code></pre>

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