NSPredicate execureFetchRequest不起作用-可能由于字符串中的空格 [英] NSPredicate execureFetchRequest not working - possibly due to spaces in string

问题描述

我正在尝试在CoreData中搜索与recordId和字符串名称均匹配的对象，但它并不总是找到该对象。
例如，我正在搜索一个ID为1000且名称为 The Brown Family的对象（注意 The和 Brown之间的2个空格）。
如果我使用：

I am trying to search in CoreData for an object that matches both a recordId and a string name, but it doesn't always find the object. For example, I an searching for an object with id 1000 and name "The Brown Family" (note the 2 spaces between "The" and "Brown"). If I use:

NSPredicate *pred = [NSPredicate predicateWithFormat:@"(recordId == %@") AND (name like[cd] %@)", recordId, name];

，具有recordId = 1000和name = The Brown Family，获取请求返回nil。
如果我使用：

with recordId=1000 and name="The Brown Family", the fetch request returns nil. If I use:

NSPredicate *pred = [NSPredicate predicateWithFormat:@"(recordId == %@"),   recordId];

with recordId = 1000，它将找到对象。如果我打印对象的name属性，则会得到 The Brown Family。
因此，该对象具有正确的ID和名称，但我的fetchRequest失败了。我做错了吗？

with recordId=1000, it finds the object. If I print the object's name property, I get "The Brown Family". So the object is there with the correct id and name, but my fetchRequest fails. What am I doing wrong?

推荐答案

您可能需要将值用单引号引起来...

You might need to enclose the value in single quotes...

NSPredicate *pred = [NSPredicate predicateWithFormat:@"(recordId == %@) AND (name like[cd] '%@')", recordId, name];

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