add ReturnIndex option

.gitignore

@@ -1 +1,2 @@
 *.test
+.idea/

input.go

@@ -122,6 +122,10 @@ type Options struct {
 	// By default, MaskVal is asterisk(*).
 	MaskVal string
 
+	// ReturnIndex is used to return the index instead of the value when using Select.
+	// By default, ReturnIndex is false.
+	ReturnIndex bool
+
 	// ValidateFunc is function to do extra validation of user
 	// input string. By default, it does nothing (just returns nil).
 	ValidateFunc ValidateFunc

select.go

@@ -130,7 +130,15 @@ func (i *UI) Select(query string, list []string, opts *Options) (string, error)
 		}
 
 		// Reach here means it gets ideal input.
-		resultStr = list[n-1]
+
+		// Check if the return will be the value or the index.
+		returnIndex := opts.ReturnIndex
+		if !returnIndex {
+			resultStr = list[n-1]
+		} else {
+			resultStr = line
+		}
+
 		break
 	}