create-fetch-hooks/dist/utils/dataToFormData.js

A simple and powerful custom React hook (useApi) that simplifies API requests with automatic loading and error states. Ideal for clean and maintainable data fetching in React components.

// export type FormDataValue =
//   | string
//   | Blob
//   | Blob[]
//   | string[]
//   | File
//   | File[]
//   | Uint8Array
//   | Uint8Array[]
//   | null
//   | undefined
//   | FormDataValueObject
//   | FormDataValue[];
export function dataToFormData(data, removeNulls = false, parentKey = null, formData = new FormData()) {
    Object.entries(data).forEach(([key, value]) => {
        const fullKey = parentKey ? `${parentKey}[${key}]` : key;
        if (value === null || value === undefined) {
            if (!removeNulls) {
                formData.append(fullKey, "");
            }
            return;
        }
        if (Array.isArray(value)) {
            value.forEach((v, index) => {
                if (v === null || v === undefined)
                    return;
                const arrayKey = `${fullKey}[${index}]`;
                if (typeof v === "object" &&
                    !(v instanceof Blob) &&
                    !(v instanceof File) &&
                    !(v instanceof Uint8Array)) {
                    dataToFormData(v, removeNulls, arrayKey, formData);
                }
                else {
                    const isBlob = v instanceof Blob;
                    const isFile = v instanceof File;
                    const isUint8Array = v instanceof Uint8Array;
                    const val = isBlob || isFile
                        ? v
                        : isUint8Array
                            ? new Blob([new Uint8Array(value)])
                            : String(v);
                    formData.append(arrayKey, val);
                }
            });
        }
        else if (typeof value === "object" &&
            !(value instanceof Blob) &&
            !(value instanceof File) &&
            !(value instanceof Uint8Array)) {
            dataToFormData(value, removeNulls, fullKey, formData);
        }
        else {
            const isBlob = value instanceof Blob;
            const isFile = value instanceof File;
            const isUint8Array = value instanceof Uint8Array;
            const val = isBlob || isFile
                ? value
                : isUint8Array
                    ? new Blob([new Uint8Array(value)])
                    : String(value);
            formData.append(fullKey, val);
        }
    });
    return formData;
}