Null string variant cannot be converted to a character.

不能将空字符串变量转换为字符。

youdao

To let users select the file to import, specify a null string for filename.

为了让用户选择要导入的文件，文件名指定一个空字符串。

youdao

However, the.net client de-serializes it into a zero length string instead of a null string.

然而，. NET客户端将其反序列化成长度为0的字符串而不是空的字符串。

youdao

NULL If a get string returns null, that pretty much means something went wrong and there are a few things that could go wrong.

如果GetSting返回，大致上表示的是出错了,这里有几种出错的地方。

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