updated function to be able to take booleans as values

src/index.ts

@@ -1,7 +1,9 @@
 export type QueryString = string;
 
+export type ValidValue = string | number | boolean;
+
 export interface ParamObject {
-  [key: string]: string | number | (string | number)[];
+  [key: string]: ValidValue | ValidValue[];
 }
 
 export enum ParamError {
@@ -24,6 +26,7 @@ function checkIfObjectisValid(paramObject: ParamObject): void {
     if (
       typeof value !== "string" &&
       typeof value !== "number" &&
+      typeof value !== "boolean" &&
       !Array.isArray(value) &&
       value !== undefined &&
       value !== null
@@ -47,8 +50,12 @@ function checkIfObjectisValid(paramObject: ParamObject): void {
   });
 }
 
-export function isValidValue(val: number | string) {
-  return typeof val === "number" || (typeof val === "string" && !!val.length);
+export function isValidValue(val: ValidValue) {
+  return (
+    typeof val === "number" ||
+    (typeof val === "string" && !!val.length) ||
+    typeof val === "boolean"
+  );
 }
 
 /** This function removes any undefined/null properties from an object as well as any undefined/null values in any arrays on the object */
@@ -69,7 +76,7 @@ export function removeEmpty(
         delete current[key];
       }
     } else if (isValidValue(obj[key])) {
-      current[key] = obj[key];
+      current[key] = obj[key].toString();
     }
 
     return current;

tests/index.spec.ts

@@ -32,6 +32,17 @@ test(`It returns a query string when an integer is passed in`, t => {
   t.end();
 });
 
+test(`It returns a query string when a boolean is passed in`, t => {
+  const object = {
+    a: false
+  };
+
+  const result = objToQueryString(object);
+
+  t.equal(result, "a=false");
+  t.end();
+});
+
 test(`It can handle an integer as a key`, t => {
   const object = {
     3: 1
@@ -132,19 +143,20 @@ test(`It will handle an array of strings by creating the format 'arrayName[]=val
   t.end();
 });
 
-test(`It will handle integers, strings, and multiple array of strings of strings/numbers by creating the format 'arrayName[]=val1&arrayName[]=val2`, t => {
+test(`It will handle integers, strings, booleans, and multiple array of strings of strings/numbers by creating the format 'arrayName[]=val1&arrayName[]=val2`, t => {
   const object = {
     a: ["a string", "the second string", "the third string", 2],
     b: 3,
     c: "a string by itself",
-    4: [1, "more", "array of stuff"]
+    4: [1, "more", "array of stuff"],
+    d: false
   };
 
   const result = objToQueryString(object);
 
   t.equal(
     result,
-    "4[]=1&4[]=more&4[]=array%20of%20stuff&a[]=a%20string&a[]=the%20second%20string&a[]=the%20third%20string&a[]=2&b=3&c=a%20string%20by%20itself"
+    "4[]=1&4[]=more&4[]=array%20of%20stuff&a[]=a%20string&a[]=the%20second%20string&a[]=the%20third%20string&a[]=2&b=3&c=a%20string%20by%20itself&d=false"
   );
   t.end();
 });