The initial logic behind the Search button is very similar to the first example: we check that the text box doesn't contain an empty string prior to invoking the web service.

在Search按钮背后的初始逻辑是类似于第一个实例：我们在调用 Web 服务之前，检查文本框是不是一个空字符串。

youdao

The initial logic behind the Search button is very similar to the first example: we check that the text box doesn't contain an empty string prior to invoking the web service.

在Search按钮背后的初始逻辑是类似于第一个实例：我们在调用 Web 服务之前，检查文本框是不是一个空字符串。

youdao