wp_get_current_user()

<?php // 例
$user = wp_get_current_user();
echo $user->ID;            // ユーザーID
echo $user->user_login;    // ログインID
echo $user->user_nicename; // ニックネーム
echo $user->user_email;    // メールアドレス
echo $user->user_status;   // ユーザーステータス
echo $user->display_name;  // WordPress上の表示名

  {
    "data": {
      "ID": "1",
      "user_login": "psboss",
      "user_pass": "$P$BVxWPYnkPeGglMfZRgxFaw0NwnrREq0",
      "user_nicename": "psboss",
      "user_email": "parallel.soft@gmail.com",
      "user_url": "https:\/\/parallel-soft.com",
      "user_registered": "2020-12-11 06:53:54",
      "user_activation_key": "1659752220:$P$BvyTxV0.CkdxBjLL0wwXIFAsHQCqyk0",
      "user_status": "0",
      "display_name": "管理者"
    },
    "ID": 1,
    "caps": {
      "administrator": true
    },
    "cap_key": "wpecbf98capabilities",
    "roles": [
      "administrator"
    ],
    "allcaps": {
      "switch_themes": true,
      "edit_themes": true,
      "activate_plugins": true,
      "edit_plugins": true,
      "edit_users": true,
      "edit_files": true,
      "manage_options": true,
      "moderate_comments": true,
      "manage_categories": true,
      "manage_links": true,
      "upload_files": true,
      "import": true,
      "unfiltered_html": true,
      "edit_posts": true,
      "edit_others_posts": true,
      "edit_published_posts": true,
      "publish_posts": true,
      "edit_pages": true,
      "read": true,
      "level_10": true,
      "level_9": true,
      "level_8": true,
      "level_7": true,
      "level_6": true,
      "level_5": true,
      "level_4": true,
      "level_3": true,
      "level_2": true,
      "level_1": true,
      "level_0": true,
      "edit_others_pages": true,
      "edit_published_pages": true,
      "publish_pages": true,
      "delete_pages": true,
      "delete_others_pages": true,
      "delete_published_pages": true,
      "delete_posts": true,
      "delete_others_posts": true,
      "delete_published_posts": true,
      "delete_private_posts": true,
      "edit_private_posts": true,
      "read_private_posts": true,
      "delete_private_pages": true,
      "edit_private_pages": true,
      "read_private_pages": true,
      "delete_users": true,
      "create_users": true,
      "unfiltered_upload": true,
      "edit_dashboard": true,
      "update_plugins": true,
      "delete_plugins": true,
      "install_plugins": true,
      "update_themes": true,
      "install_themes": true,
      "update_core": true,
      "list_users": true,
      "remove_users": true,
      "promote_users": true,
      "edit_theme_options": true,
      "delete_themes": true,
      "export": true,
      "manage_woocommerce": true,
      "view_woocommerce_reports": true,
      "edit_product": true,
      "read_product": true,
      "delete_product": true,
      "edit_products": true,
      "edit_others_products": true,
      "publish_products": true,
      "read_private_products": true,
      "delete_products": true,
      "delete_private_products": true,
      "delete_published_products": true,
      "delete_others_products": true,
      "edit_private_products": true,
      "edit_published_products": true,
      "manage_product_terms": true,
      "edit_product_terms": true,
      "delete_product_terms": true,
      "assign_product_terms": true,
      "edit_shop_order": true,
      "read_shop_order": true,
      "delete_shop_order": true,
      "edit_shop_orders": true,
      "edit_others_shop_orders": true,
      "publish_shop_orders": true,
      "read_private_shop_orders": true,
      "delete_shop_orders": true,
      "delete_private_shop_orders": true,
      "delete_published_shop_orders": true,
      "delete_others_shop_orders": true,
      "edit_private_shop_orders": true,
      "edit_published_shop_orders": true,
      "manage_shop_order_terms": true,
      "edit_shop_order_terms": true,
      "delete_shop_order_terms": true,
      "assign_shop_order_terms": true,
      "edit_shop_coupon": true,
      "read_shop_coupon": true,
      "delete_shop_coupon": true,
      "edit_shop_coupons": true,
      "edit_others_shop_coupons": true,
      "publish_shop_coupons": true,
      "read_private_shop_coupons": true,
      "delete_shop_coupons": true,
      "delete_private_shop_coupons": true,
      "delete_published_shop_coupons": true,
      "delete_others_shop_coupons": true,
      "edit_private_shop_coupons": true,
      "edit_published_shop_coupons": true,
      "manage_shop_coupon_terms": true,
      "edit_shop_coupon_terms": true,
      "delete_shop_coupon_terms": true,
      "assign_shop_coupon_terms": true,
      "wf2fa_activate_2fa_self": true,
      "wf2fa_activate_2fa_others": true,
      "wf2fa_manage_settings": true,
      "administrator": true
    },
    "filter": null
  }