Added a getStatusCode method. (#28)

* Added a getStatusCode method.

* Updated documentation and definition for getStatusCode

README.md

@@ -26,6 +26,12 @@ response
 	.send({
 		error: HttpStatus.getStatusText(HttpStatus.INTERNAL_SERVER_ERROR)
 	});
+
+response
+	.status(HttpStatus.getStatusCode('Server Error'))
+	.send({
+		error: 'Server Error'
+	});
 ```
 
 ## Codes
@@ -107,14 +113,24 @@ response
 	.send({
 		error: HttpStatus.getStatusText(HttpStatus.INTERNAL_SERVER_ERROR)
 	})
+
+response
+	.status(HttpStatus.getStatusCode('Server Error'))
+	.send({
+		error: 'Server Error'
+	})
 ```
 
 Option 2: Selective import
 
 ```typescript
-import { OK, getStatusText } from 'http-status-codes'
+import { OK, getStatusText, getStatusCode } from 'http-status-codes'
 
 response
 	.status(OK)
 	.send(getStatusText(OK))
+
+response
+	.status(getStatusCode('Server Error')
+	.send('Server Error')
 ```

index.d.ts

@@ -327,5 +327,14 @@ export declare const USE_PROXY = 305;
  * Convert the numeric status code to its appropriate title.
  * @param statusCode One of the available status codes in this package
  * @returns {String} The associated title of the passed status code
+ * @throws {Error} The status code does not exist
  */
 export declare function getStatusText(statusCode: number): string;
+
+/**
+ * Convert the status reason phrase to its appropriate numeric value
+ * @param reasonPhrase One of the available reason phrases in this package
+ * @returns {Number} The associated status code of the passed reason phrase
+ * @throws {Error} The reason phrase does not exist
+ */
+export declare function getStatusCode(reasonPhrase: string): number;

index.js

@@ -74,3 +74,13 @@ exports.getStatusText = function(statusCode) {
     throw new Error("Status code does not exist: " + statusCode);
   }
 };
+
+exports.getStatusCode = function(reasonPhrase) {
+  for (key in statusCodes) {
+    if (statusCodes[key] === reasonPhrase) {
+      return parseInt(key, 10);
+    }
+  }
+  throw new Error("Reason phrase does not exist: " + reasonPhrase);
+};
+