JSFiddle - React, Tailwind, and code Playground
HTML
<div class="floortitle">Temperaturen</div>
<div class='tempfield'>
<div class='picpos'></div>
<div>
<div class='tempbox' id='Temp1'>11°C</div>
</div>
<div>
<div class='tempbox' id='Temp2'>12°C</div>
</div>
<div>
<div class='tempbox' id='Temp3'>13°C</div>
</div>
</div>
JavaScript
var string="\
02.10.2013;17:40:59;Temp 1;17;\
02.10.2013;17:40:59;Temp 2;27;\
02.10.2013;17:40:59;Temp 3;34;\
02.10.2013;17:40:59;Temp 4;46;\
02.10.2013;17:40:59;Temp 5;53;\
02.10.2013;17:40:59;Temp 6;61;";
var tempResult={};
string.replace(/Temp (\d);(\d+)/gm,function($0,$1,$2){tempResult[$1]=$2;});
for (var i=1;i<4;i++) {
document.getElementById("Temp"+i).innerHTML=tempResult[i]+"°C";
}