function zmien_styl(blok, tekst) {

   var txtarea = document.getElementById(blok);
   var selStart = txtarea.selectionStart;
   var selEnd = txtarea.selectionEnd;
   
   document.getElementById(blok).value=
   (txtarea.value).substring(0,selStart)+
   "<"+tekst+">"+(txtarea.value).substring(selStart, selEnd)+"</"+tekst+">" +
   (txtarea.value).substring(selEnd,txtarea.value.length);
}
function linia(blok) {

var txtarea = document.getElementById(blok);
var selStart = txtarea.selectionStart;
var selEnd = txtarea.selectionEnd;
var length = ((txtarea.value).substring(selStart, selEnd)).length;
var tekst = "----------------------------------------------------------------------"

document.getElementById(blok).value = (txtarea.value).substring(0,selStart) + tekst + (txtarea.value).substring(selEnd,txtarea.value.length);


document.getElementById(blok).focus();

}
function email(blok) {

   var txtarea = document.getElementById(blok);
   var selStart = txtarea.selectionStart;
   var selEnd = txtarea.selectionEnd;
   
   document.getElementById(blok).value=
   (txtarea.value).substring(0,selStart)+
   "<a href=\"mailto: "+(txtarea.value).substring(selStart, selEnd)+"\" target=\"_blank\">" +(txtarea.value).substring(selStart, selEnd)+"</a>"+
   (txtarea.value).substring(selEnd,txtarea.value.length);
}
function web(blok) {

   var txtarea = document.getElementById(blok);
   var selStart = txtarea.selectionStart;
   var selEnd = txtarea.selectionEnd;
   
   document.getElementById(blok).value=
   (txtarea.value).substring(0,selStart)+
   "<a href=\"http://"+(txtarea.value).substring(selStart, selEnd)+"\" target=\"_blank\">" +(txtarea.value).substring(selStart, selEnd)+"</a>"+
   (txtarea.value).substring(selEnd,txtarea.value.length);
}