Question

需要

我必须找到rec_name的记录是＆＃34; Apple 256GB Macbook＆＃34; ＆安培; isActive == true。

获取请求

fetchRequest.predicate = NSPredicate(format: "rec_name LIKE[cd] *%@* AND rec_name LIKE[cd] *%@* AND isActive = %@","apple","macbook",true)

错误

Unable to parse the format string "rec_name LIKE[cd] *%@* AND rec_name LIKE[cd] *%@* AND isActive = %@"

谢谢，

Answer 1

问题是由于*%@* %@之间的*未被字符串参数替换，因此NSPredicate无法进行查询LIKE *apple* }和LIKE *macbook*您需要做的是使用通配符创建搜索字符串，而使用Like只需使用%@，同时@Vadian建议使用数字而不是Bool。

let searchkeyword1 = "apple"
let searchkeyword2 = "macbook"

//Make search string wildcards charaters
let searchString1 = "*\(searchkeyword1)*"
let searchString2 = "*\(searchkeyword2)*"

fetchRequest.predicate = NSPredicate(format: "rec_name LIKE[cd] %@ AND rec_name LIKE[cd] %@ AND isActive = %@", searchString1,searchString2, true as NSNumber)

此处的击球选项是你可以使用CONTAINS而不需要使用通配符。

fetchRequest.predicate = NSPredicate(format: "rec_name CONTAINS[cd] %@ AND rec_name CONTAINS[cd] %@ AND isActive = %@", "apple","macbook", true as NSNumber)

如果你想找到所有以apple开头的记录并以macbook结尾，你可以再做一件事，那么你可以简单地使用BEGINSWITH和ENDSWITH

fetchRequest.predicate = NSPredicate(format: "rec_name BEGINSWITH[cd] %@ AND rec_name ENDSWITH[cd] %@ AND isActive = %@", "apple","macbook", true as NSNumber)

Answer 2

试试这个

fetchRequest.predicate =  NSPredicate(format: "rec_name LIKE[cd] %@ AND rec_name LIKE[cd] %@ AND isActive = %@","apple","macbook",NSNumber(booleanLiteral: true))

Answer 3

您需要设置如下的谓词查询：

fetchRequest.predicate = NSPredicate(format: "rec_name == %@ AND isActive == %@" , "Apple 256GB Macbook", NSNumber(booleanLiteral: true))

如果您正在寻找完美匹配，我认为我们不需要使用Like。

Answer 4

试试这个

NSPredicate(format: "rec_name == %@ AND rec_name == %@ AND isActive = %d","apple","macbook",true)

核心数据获取谓词的请求错误

4 个答案: