Split string in JavaScript and detect line break

var str = `your text
           that spans
           multiple lines`

// Split the string on \n or \r characters
var separateLines = str.split(/\r?\n|\r|\n/g);

alert("Total number of separate lines is: " + separateLines.length);

var str = `your text
           that spans
           multiple lines`

// Split the string on \n or \r characters
var separateLines = str.match(/[^\r\n]+/g);
 
alert("Total number of separate lines is: " + separateLines.length);