Fetch content from multiple higher level of parent page when content in current page is empty.

temp.rightContent is fetching content of current page. Now check if this is empty we'll fetch from the parent page. This way we'll check again parent-parent i.e. grand parent page as so on. To achieve this i've take leveluid into count. We can apply different way as well. As per example below Typoscript object `lib.column_right_parent` is containing our required content.

temp.rightContent.current = CONTENT
temp.rightContent.current  {
  table = tt_content
  select.pidInList.data = leveluid : -1
  #select.pidInList.data = 1
  select.orderBy = sorting
  select.where = colPos= 2
  select.languageField = sys_language_uid
}

lib.column_right_parent < temp.rightContent.current
lib.column_right_parent.stdWrap.ifEmpty.cObject < temp.rightContent.current
lib.column_right_parent.stdWrap.ifEmpty.cObject {
  select.pidInList.data = leveluid : -2
  stdWrap.ifEmpty.cObject  < temp.rightContent.current
  stdWrap.ifEmpty.cObject {
    select.pidInList.data = leveluid : -3
    stdWrap.ifEmpty.cObject  < temp.rightContent.current
    stdWrap.ifEmpty.cObject {
      select.pidInList.data = leveluid : -4
        stdWrap.ifEmpty.cObject  < temp.rightContent.current
        stdWrap.ifEmpty.cObject {
          select.pidInList.data = leveluid : -5
      }
    }
  }
}

Typoscript to generate SELECT box (option-select) for page tree.

This typoscript below will generate a option select box for page tree or dropdown box for a page tree.
One simple javascript code has been added to make this select box active.
This example below is just an idea. We can easily customize this according to our need.

lib.field_menu_os = HMENU
lib.field_menu_os.entryLevel = 1
lib.field_menu_os {  
     wrap = <select id="menu_option_select" name="menu_option_select" size="1" onChange="javascript:_go_to_page(this.value);" >|</select>
     1 = TMENU
     1 {
       expAll = 1
       noBlur = 1
       NO {      
         stdWrap.dataWrap = <option value="{field:uid}">
         allWrap = |</option>
         doNotLinkIt = 1
       }
       # Inherit the 'allWrap' and 'doNotLinkIt' settings from the NO part
       CUR < .NO
       CUR = 1
       CUR {
         stdWrap.dataWrap = <option value="{field:uid}" selected="selected">
       }
     }
     2 = TMENU
     2 {
       expAll = 1
       noBlur = 1
       NO {
         stdWrap.dataWrap = <option value="{field:uid}">&nbsp;-&nbsp;
         allWrap = |</option>
         doNotLinkIt = 1
       }
       # Inherit the 'allWrap' and 'doNotLinkIt' settings from the NO part
       CUR < .NO
       CUR = 1
       CUR {
         stdWrap.dataWrap = <option value="{field:uid}" selected="selected">&nbsp;-&nbsp;
       }
     }
     3 = TMENU
     3 {
       expAll = 1
       noBlur = 1
       NO {
         stdWrap.dataWrap = <option value="{field:uid}">&nbsp;&nbsp;-&nbsp;&nbsp;
         allWrap = |</option>
         doNotLinkIt = 1
       }
       # Inherit the 'allWrap' and 'doNotLinkIt' settings from the NO part
       CUR < .NO
       CUR = 1
       CUR {
         stdWrap.dataWrap = <option value="{field:uid}" selected="selected">&nbsp;&nbsp;-&nbsp;&nbsp;
       }
     }    
  }

Simple one line of javascript will do the job easily. We can take help of jQuery too.

      function _go_to_page(selected_page_id){
  document.location.href='index.php?id='+selected_page_id;
 } 

Various TMENU wrap functions.

Availability of various wrap functions for TMENU and show them level-wise.
Here its a good example with some wrap functions and places to use them while we write typoscript for texual menu.

<wrapItemAndSub>
 <allWrap>
 <allStdWrap>
 <before>
 <beforeImg beforeImgTagParams>
 <linkWrap>
  <A href=… ATagParams TITLE=ATagTitle>
   <stdWrap.dataWrap> TMENUITEM </stdWrap>
  </A>
 </linkWrap>
 <after>
 </allStdWrap>
 </allWrap>
  UNTERMENU 1
  UNTERMENU 2
</wrapItemAndSub>

For more detail description please visit
https://docs.typo3.org/typo3cms/TyposcriptReference/MenuObjects/Tmenu/Index.html

Typoscript code to display content of this page - if empty fetch from specific page of TYPO3.

We'll fetch content from current page and check if this is empty we'll fetch content from page id = 38.
In the example below  `myContent` is fetching our default content. If this is empty we'll show content by `myContentBackup`  and this way we can go on ...

lib.myContent = CONTENT
 lib.myContent < styles.content.getLeft
 lib.myContent.stdWrap.ifEmpty.cObject < lib.myContentBackup
 lib.myContentBackup = CONTENT
 lib.myContentBackup {
    table = tt_content
        select {
            # specify the page id
            pidInList = 38
            # specify the column to fetch
            where = colPos = 3
            #for latest version language field is not required
            languageField = sys_language_uid
        }
}