尝试*ngIf="!overwrite && !!saveName"将saveName转换为布尔值

TypeScript给出该错误的原因大致是:您在应该使用布尔值的地方使用了字符串.

The reason TypeScript gives for the error is roughly: you are using a string where you should be using a boolean.

我认为它仅在这种情况下发生的原因是，如果您拥有true || anything，则仅会评估第一个(因为如果第一个为true，则整个表达式将为true，而与其余情况无关)

The reason I think that it only happens in that circumstance is because if you have true || anything only the first will be evaluated (because if the first is true the whole expression will true regardless of the rest)