GODRIVER-2816 Add documentation Example for primitive.Regex Usage (#1245)

Author: prestonvasquez

mongo/crud_examples_test.go

@@ -1071,3 +1071,85 @@ func ExampleIndexView_List() {
 	}
 	fmt.Println(results)
 }
+
+func ExampleCollection_Find_primitiveRegex() {
+	ctx := context.TODO()
+	clientOptions := options.Client().ApplyURI("mongodb://localhost:27017")
+
+	// Connect to a mongodb server.
+	client, err := mongo.Connect(ctx, clientOptions)
+	if err != nil {
+		panic(err)
+	}
+
+	defer client.Disconnect(ctx)
+
+	type Pet struct {
+		Type string `bson:"type"`
+		Name string `bson:"name"`
+	}
+
+	// Create a slice of documents to insert. We will lookup a subset of
+	// these documents using regex.
+	toInsert := []interface{}{
+		Pet{Type: "cat", Name: "Mo"},
+		Pet{Type: "dog", Name: "Loki"},
+	}
+
+	coll := client.Database("test").Collection("test")
+
+	if _, err := coll.InsertMany(ctx, toInsert); err != nil {
+		panic(err)
+	}
+
+	// Create a filter to find a document with key "name" and any value that
+	// starts with letter "m". Use the "i" option to indicate
+	// case-insensitivity.
+	filter := bson.D{{"name", primitive.Regex{Pattern: "^m", Options: "i"}}}
+
+	_, err = coll.Find(ctx, filter)
+	if err != nil {
+		panic(err)
+	}
+}
+
+func ExampleCollection_Find_regex() {
+	ctx := context.TODO()
+	clientOptions := options.Client().ApplyURI("mongodb://localhost:27017")
+
+	// Connect to a mongodb server.
+	client, err := mongo.Connect(ctx, clientOptions)
+	if err != nil {
+		panic(err)
+	}
+
+	defer client.Disconnect(ctx)
+
+	type Pet struct {
+		Type string `bson:"type"`
+		Name string `bson:"name"`
+	}
+
+	// Create a slice of documents to insert. We will lookup a subset of
+	// these documents using regex.
+	toInsert := []interface{}{
+		Pet{Type: "cat", Name: "Mo"},
+		Pet{Type: "dog", Name: "Loki"},
+	}
+
+	coll := client.Database("test").Collection("test")
+
+	if _, err := coll.InsertMany(ctx, toInsert); err != nil {
+		panic(err)
+	}
+
+	// Create a filter to find a document with key "name" and any value that
+	// starts with letter "m". Use the "i" option to indicate
+	// case-insensitivity.
+	filter := bson.D{{"name", bson.D{{"$regex", "^m"}, {"$options", "i"}}}}
+
+	_, err = coll.Find(ctx, filter)
+	if err != nil {
+		panic(err)
+	}
+}