Update and rename decamelize.md to convert-string-from-camelcase.md

snippets/convert-string-from-camelcase.md

@@ -0,0 +1,13 @@
+### Convert string from camelcase
+
+Use `replace()` to remove underscores, hyphens and spaces and convert words to camelcase.
+Omit the scond argument to use a default separator of '_'.
+
+```js
+const fromCamelCase = (str, separator = '_') => 
+  str.replace(/([a-z\d])([A-Z])/g, '$1' + separator + '$2')
+    .replace(/([A-Z]+)([A-Z][a-z\d]+)/g, '$1' + separator + '$2').toLowerCase();
+// decamelize('someDatabaseFieldName', ' ') -> 'some database field name'
+// decamelize('someLabelThatNeedsToBeCamelized', '-') -> 'some-label-that-needs-to-be-camelized'
+// decamelize('someJavascriptProperty', '_') -> 'some_javascript_property'
+```