Added #175 added contol char handler in convert.ts

Author: rg911

src/core/format/Convert.ts

@@ -168,7 +168,12 @@ export class Convert {
         const rawString = Convert.rstr2utf8(input);
         let result = '';
         for (let i = 0; i < rawString.length; i++) {
-            result += rawString.charCodeAt(i).toString(16);
+            if (rawString.charCodeAt(i) < 16) {
+                // Add insignificant zero for control chars (0x00 - 0x0f)
+                result += '0' + rawString.charCodeAt(i).toString(16);
+            } else {
+                result += rawString.charCodeAt(i).toString(16);
+            }
         }
         return result;
     }

test/core/format/Convert.spec.ts

@@ -233,6 +233,16 @@ describe('convert', () => {
             // Assert:
             expect(actual).to.equal('e58588e7a7a6e585a9e6bca2');
         });
+
+        it('utf8 text to hex with control char', () => {
+            // Act:
+            const test  = String.fromCodePoint(0x0f) + ' Hello World!';
+            console.log('UTF8', test);
+            const actual = convert.utf8ToHex(test);
+
+            // Assert:
+            expect(actual).to.equal('0f2048656c6c6f20576f726c6421');
+        });
     });
 
     describe('signed <-> unsigned byte', () => {