function formatHL7String(str) { var hl7String = str.replace(/\\/g, '\\E\\'); hl7String = hl7String.replace(/\|/g, '\\F\\'); hl7String = hl7String.replace(/\^/g, '\\S\\'); hl7String = hl7String.replace(/~/g, '\\R\\'); hl7String = hl7String.replace(/&/g, '\\T\\'); return hl7String; } console.log(" \\ | ^ ~ & "); console.log(formatHL7String(" \\ | ^ ~ & ")); function parseHL7String(hl7String) { var parsedString = hl7String.replace(/\\F\\/g, '\|'); parsedString = parsedString.replace(/\\S\\/g, '^'); parsedString = parsedString.replace(/\\R\\/g, '~'); parsedString = parsedString.replace(/\\T\\/g, '&'); parsedString = parsedString.replace(/\\E\\/g, '\\'); return parsedString; } console.log(parseHL7String(formatHL7String(" \\ | ^ ~ & ")));