By default, the BackgroundExt property is empty. Using the BackgroundExt property you have unlimited options to show any HTML text, images, colors, EBNs, patterns, frames anywhere on the object's background. For instance, let's say you need to display more colors on the object's background, or just want to display an additional caption or image to a specified location on the object's background. The EBN String Format defines the parts of the EBN to be applied on the object's background. The EBN is a set of UI elements that are built as a tree where each element is anchored to its parent element. Use the BackgroundExtValue property to change at runtime any UI property for any part that composes the EBN String Format. The BackgroundExt property is applied right after setting the object's backcolor, and before drawing the default object's captions, icons or pictures.  

The following screen shot shows a few possibilities you can have using the BackgroundExt property:

Easy samples:

• "[pattern=6]", shows the BDiagonal pattern on the object's background.

  

• "[frame=RGB(255,0,0),framethick]", draws a red thick-border around the object.

  

• "[frame=RGB(255,0,0),framethick,pattern=6,patterncolor=RGB(255,0,0)]", draws a red thick-border around the object, with a patter inside.

  

• "[[patterncolor=RGB(255,0,0)](none[(4,4,100%-8,100%-8),pattern=0x006,patterncolor=RGB(255,0,0),frame=RGB(255,0,0),framethick])]", draws a red thick-border around the object, with a patter inside, with a 4-pixels wide padding:

  

• "top[4,back=RGB(0,0,255)]", draws a blue line on the top side of the object's background, of 4-pixels wide.

  

• "[text=`caption`,align=0x22]", shows the caption string aligned to the bottom-right side of the object's background.

  

• "[text=`<img>flag</img>`,align=0x11]" shows the flag picture and the sweden string aligned to the bottom side of the object.

  

• "left[10,back=RGB(255,0,0)]", draws a red line on the left side of the object's background, of 10-pixels wide.

  

• "bottom[50%,pattern=6,frame]", shows the BDiagonal pattern with a border arround on the lower-half part of the object's background.

  

• "root[text=`caption <b>2`,align=0x22](client[text=`caption <b>1`,align=0x20])", shows the caption 1 aligned to the bottom-left side, and the caption 2 to the bottom-right side

  

The Exontrol's eXButton WYSWYG Builder helps you to generate or view the EBN String Format, in the To String field as shown in the following screen shot: 

The To String field of the EBN Builder defines the EBN String Format that can be used on BackgroundExt property.

The EBN String Format syntax in BNF notation is defined like follows:

<EBN> ::= <elements> | <root> "(" [<elements>] ")"
<elements> ::= <element> [ "," <elements> ]
<root> ::= "root" [ <attributes> ] | [ <attributes> ]
<element> ::= <anchor> [ <attributes> ] [ "(" [<elements>] ")" ]
<anchor> ::= "none" | "left" | "right" | "client" | "top" | "bottom"
<attributes> ::= "[" [<client> ","] <attribute> [ "," <attributes> ] "]"
<client> ::= <expression> | <expression> "," <expression> "," <expression> "," <expression>
<expression> ::= <number> | <number> "%"
<attribute> ::= <backcolor> | <text> | <wordwrap> | <align> | <pattern> | <patterncolor> | <frame> | <framethick> | <data> | <others>
<equal> ::= "="
<digit> ::= 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9
<decimal> ::= <digit><decimal>
<hexadigit> ::= <digit> | "A" | "B"  "C" | "D" | "E"  "F"
<hexa> ::= <hexadigit><hexa>
<number> ::= <decimal> | "0x" <hexa>
<color> ::= <rgbcolor> | number
<rgbcolor> ::= "RGB" "(" <number> "," <number> "," <number> ")"
<string> ::= "`" <characters> "`" | "'" <characters> "'" | " <characters> "
<characters> ::= <char>|<characters>
<char> ::= <any_character_excepts_null>
<backcolor> ::= "back" <equal> <color>
<text> ::= "text" <equal> <string>
<align> ::= "align" <equal> <number>
<pattern> ::= "pattern" <equal> <number>
<patterncolor> ::= "patterncolor" <equal> <color>
<frame> ::= "frame" <equal> <color>
<data> ::= "data" <equal> <number> | <string>
<framethick> ::= "framethick"
<wordwrap> ::= "wordwrap"

Others like: pic, stretch, hstretch, vstretch, transparent, from, to are reserved for future use only.