Be able to use a server relative folder path.

docs/documentation/docs/controls/DynamicForm.md

@@ -66,7 +66,7 @@ The `DynamicForm` can be configured with the following properties:
 | validationErrorDialogProps | IValidationErrorDialogProps | no | Specifies validation error dialog properties |
 | customIcons | { [ columnInternalName: string ]: string } | no | Specifies custom icons for the form. The key of this dictionary is the column internal name, the value is the Fluent UI icon name. | 
 | storeLastActiveTab | boolean | no |  When uploading files: Specifies if last active tab will be stored after the Upload panel has been closed. Note: the value of selected tab is stored in the queryString hash. Default - `true` |
-| folderPath | string | no | Library relative folder to create the item in. This option is only available for document libraries and works only when the contentTypeId is specified and has a base type of type Document or Folder. Defaults to the root folder. |
+| folderPath | string | no | Server relative or library relative folder to create the item in. This option is only available for document libraries and works only when the contentTypeId is specified and has a base type of type Document or Folder. Defaults to the root folder of the library. |
 
 ## Validation Error Dialog Properties `IValidationErrorDialogProps`
 | Property | Type | Required | Description |

src/controls/dynamicForm/DynamicForm.tsx

@@ -1478,10 +1478,26 @@ export class DynamicForm extends React.Component<
         return 'Document';
     }
   }
-
-  private getFolderByPath = async (listRelativeFolderPath: string, rootFolder: IFolder): Promise<IFolder> => {
+
+  /**
+   * Returns a pnp/sp folder object based on the folderPath and the library the folder is in.
+   * The folderPath can be a server relative path, but should be in the same library.
+   * @param folderPath The path to the folder coming from the component properties
+   * @param rootFolder The rootFolder object of the library
+   * @returns 
+   */
+  private getFolderByPath = async (folderPath: string, rootFolder: IFolder): Promise<IFolder> => {
     const libraryFolder = await rootFolder();
-    const folder = sp.web.getFolderByServerRelativePath(`${libraryFolder.ServerRelativeUrl}/${listRelativeFolderPath}`);
+    const normalizedFolderPath = decodeURIComponent(folderPath).toLowerCase().replace(/\/$/, "");
+    const serverRelativeLibraryPath = libraryFolder.ServerRelativeUrl.toLowerCase().replace(/\/$/, "");
+
+    // In case of a server relative path in the same library, return the folder
+    if (`${normalizedFolderPath}/`.startsWith(`${serverRelativeLibraryPath}/`)) {
+      return sp.web.getFolderByServerRelativePath(normalizedFolderPath);
+    }
+
+    // In other cases, expect a list-relative path and return the folder
+    const folder = sp.web.getFolderByServerRelativePath(`${serverRelativeLibraryPath}/${normalizedFolderPath}`);
     return folder;
   };
 }