added strings to lowercase and uppercase methods snippets

Snippets/Arrays/checkItemPresentInArray.js

@@ -1,4 +1,4 @@
-/**
+/*
  * Problem: Checks whether the dish you wish to eat is available in the menu
  */
 

Snippets/Arrays/convertArrayToString.js

@@ -9,3 +9,4 @@ console.log(typeof numbers.join(",")); // string
 
 const names = ["Javascript", "Python", "PHP"];
 console.log(names.join(",")); // 'Javascript', 'Python', 'PHP'
+

Snippets/Strings/lowerCaseConverter.js

@@ -0,0 +1,7 @@
+// toLowerCase() method changes the string to lowercase letters.
+let favLanguage = "JavasCript";
+console.log(favLanguage.toLowerCase()); // javascript
+let standard = "ECMA";
+console.log(standard.toLowerCase()); // ecma
+let oneMoreLangugae = "PHP";
+console.log(oneMoreLangugae.toLowerCase()); // php

Snippets/Strings/upperCaseConverter.js

@@ -0,0 +1,7 @@
+// toUpperCase() method changes the string to upper letters.
+let favLanguage = "JavasCript";
+console.log(favLanguage.toUpperCase()); // JAVASCRIPT
+let firstName = "ECMA";
+console.log(firstName.toUpperCase()); // ECMA
+let oneMoreLangugae = "Python";
+console.log(oneMoreLangugae.toUpperCase()); // PYTHON