檢視 Exists 的原始碼

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|<center>'''Exists'''<br><img
src="https://gimg2.baidu.com/image_search/src=http%3A%2F%2Fimg.jbzj.com%2Ffile_images%2Farticle%2F202106%2F2021060310432441.png&refer=http%3A%2F%2Fimg.jbzj.com&app=2002&size=f9999,10000&q=a80&n=0&g=0n&fmt=auto?sec=1672065021&t=f3c8c69a7e2ee6da86506513c6e2b8a8 " width="280"></center><small>  圖片來自4</small> 
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'''计算机语言术语'''

'''Exists'''：如果在 Dictionary 对象中指定的记录存在，返回 True，若不存在，返回 False。语法object.Exists(key)Exists 有如下几部分：部分描述Object必需的，始终是一个 Dictionary 对象的名字，Key必需的，在 Dictionary 对象中搜索的 Key 值。

*中文名:Exists

*外文名:Exists

*作    用:检验查询是否返回数据

*定    义:存在True，不存在False

*与IN的区别:IN是不对NULL进行处理