ZodArrays
ts
const stringArray = z.array(z.string());
// equivalent
const stringArray = z.string().array();const stringArray = z.array(z.string());
// equivalent
const stringArray = z.string().array();Be careful with the .array() method. It returns a new ZodArray instance. This means the order in which you call methods matters. For instance:
ts
z.string().optional().array(); // (string | undefined)[]
z.string().array().optional(); // string[] | undefinedz.string().optional().array(); // (string | undefined)[]
z.string().array().optional(); // string[] | undefined.element
Use .element to access the schema for an element of the array.
ts
stringArray.element; // => string schemastringArray.element; // => string schema.nonempty
If you want to ensure that an array contains at least one element, use .nonempty().
ts
const nonEmptyStrings = z.string().array().nonempty();
// the inferred type is now
// [string, ...string[]]
nonEmptyStrings.parse([]); // throws: "Array cannot be empty"
nonEmptyStrings.parse(["Ariana Grande"]); // passesconst nonEmptyStrings = z.string().array().nonempty();
// the inferred type is now
// [string, ...string[]]
nonEmptyStrings.parse([]); // throws: "Array cannot be empty"
nonEmptyStrings.parse(["Ariana Grande"]); // passesYou can optionally specify a custom error message:
ts
// optional custom error message
const nonEmptyStrings = z.string().array().nonempty({
message: "Can't be empty!",
});// optional custom error message
const nonEmptyStrings = z.string().array().nonempty({
message: "Can't be empty!",
});.min/.max/.length
ts
z.string().array().min(5); // must contain 5 or more items
z.string().array().max(5); // must contain 5 or fewer items
z.string().array().length(5); // must contain 5 items exactlyz.string().array().min(5); // must contain 5 or more items
z.string().array().max(5); // must contain 5 or fewer items
z.string().array().length(5); // must contain 5 items exactlyUnlike .nonempty() these methods do not change the inferred type.