在使用discord.py的 Discord webhook时，set_thumbnail为什么会出现语法错误？

编程语言 2026-07-09

尽管当我不尝试添加 set_thumbnail 时嵌入对象发送得很顺利，但当我试图添加它时却出现错误：

from discord import SyncWebhook, Colour, Embed
import requests

ABwebhook = SyncWebhook.from_url("*url here*")


ABwebhook.send("# caption", embed = Embed(
        title = "title",
      description= "testing",
      url= "https://www.1800flowers.com/articles/flower-facts/most-beautiful-flowers",
      color= 16741208,
      set_thumbnail(url="https://thumbs.dreamstime.com/b/purple-flower-dewdrops-soft-focus-vibrant-morning-light-nature-beauty-concept-368695089.jpg")
     ))

使用这段代码会得到：

SyntaxError: positional argument follows keyword argument

然而，如果我尝试：

ABwebhook.send("# caption", embed = Embed(
        title = "title",
      description= "testing",
      url= "https://www.1800flowers.com/articles/flower-facts/most-beautiful-flowers",
      color= 16741208,

     ))
Embed.set_thumbnail(url="https://thumbs.dreamstime.com/b/purple-flower-dewdrops-soft-focus-vibrant-morning-light-nature-beauty-concept-368695089.jpg")

它会报错：

TypeError: Embed.set_thumbnail() missing 1 required positional argument: 'self'

我已经多次查看了相关文档，因此不确定是漏掉了某个导入，还是理解错了。

解决方案

更新：

A comment below pointed out that the documentation indicates:

这个函数返回类实例，以便实现链式风格的连锁调用。

所以你确实可以在把 Embed 实例传给 send() 时就这样内联实现。对 set_thumbnail() 的调用只需要在该实例上完成，而不是作为一个分离的操作。例如：

ABwebhook.send(
  "# caption",
  embed = Embed(
    title = "title",
    description = "testing",
    url = "https://www.1800flowers.com/articles/flower-facts/most-beautiful-flowers",
    color = 16741208
  ).set_thumbnail(url = "https://thumbs.dreamstime.com/b/purple-flower-dewdrops-soft-focus-vibrant-morning-light-nature-beauty-concept-368695089.jpg")
)

原始答案：

Embed 的实例是匿名的，因为它是在调用 send() 时就地作为参数创建的。所以你没有可用于调用 set_thumbnail() 的引用。

请先创建 Embed 实例。然后你可以在该实例上调用 set_thumbnail()，再将该实例传递给 send()。例如：

#Create the instance
ABembed = Embed(
  title = "title",
  description = "testing",
  url = "https://www.1800flowers.com/articles/flower-facts/most-beautiful-flowers",
  color = 16741208
)
#Set the thumbnail on the instance
ABembed.set_thumbnail(url = "https://thumbs.dreamstime.com/b/purple-flower-dewdrops-soft-focus-vibrant-morning-light-nature-beauty-concept-368695089.jpg")
#Use the instance
ABwebhook.send("# caption", embed = ABembed)

Python