JSFiddle - React, Tailwind, and code Playground

JavaScript

var str = "-#A \
This text belongs to A. \
Dummy Text of A. \
-#B \
This text belongs to B. \
Dummy Text of B. \
-#C \
This text belongs to C. \
Dummy text of C. \
-#Garbage \
This string should be ignored.. \
    ";
var str = str.split("-#");
var newStr=[];
for(var i = 0; i < str.length; i++) { 
    if(str[i] != "" && str[i].substr(0,7) != 'Garbage') newStr.push(str[i]);
}
console.log(newStr);