我试图根据其中一个字符串字段过滤数组。
nameLower和filterLower都包含NSString值,但我一直得到:
__NSCFString containsString:]: unrecognized selector sent to instance 0x7f876b79e160
-(void) filterFriendsArray:(NSString*)filter {
[_filteredFriendsArray removeAllObjects];
for (FacebookUser* user in _friendsArray)
{
NSString* nameLower = [user.user.name lowercaseString];
NSString* filterLower = [filter lowercaseString];
if ([nameLower containsString:filterLower])
[_filteredFriendsArray addObject:user];
}
_displayedFriendsArray = _filteredFriendsArray;
}
答案 0 :(得分:119)
如果您希望代码在iOS 7和iOS 8上运行,则应使用其中一个rangeOfString调用。基本上,如果返回的范围的长度为零,则子字符串不存在。
/* These methods return length==0 if the target string is not found. So, to check for containment: ([str rangeOfString:@"target"].length > 0). Note that the length of the range returned by these methods might be different than the length of the target string, due composed characters and such.
*/
- (NSRange)rangeOfString:(NSString *)aString;
- (NSRange)rangeOfString:(NSString *)aString options:(NSStringCompareOptions)mask;
- (NSRange)rangeOfString:(NSString *)aString options:(NSStringCompareOptions)mask range:(NSRange)searchRange;
- (NSRange)rangeOfString:(NSString *)aString options:(NSStringCompareOptions)mask range:(NSRange)searchRange locale:(NSLocale *)locale NS_AVAILABLE(10_5, 2_0);
显然,使用rangeOfString在类别中实现containsString是微不足道的:
@implementation NSString (Contains)
- (BOOL)myContainsString:(NSString*)other {
NSRange range = [self rangeOfString:other];
return range.length != 0;
}
@end
答案 1 :(得分:8)
将rangeOfString与NSNotFound进行比较
NSRange range = [self rangeOfString:other];
if(range.location != NSNotFound){
//do something
}
答案 2 :(得分:3)
使用以下内容:
if (![[NSString class] respondsToSelector:@selector(containsString)])
{
//ios 7
NSRange range = [mystring rangeOfString:other];
if(range.location != NSNotFound){
//do something
}
}
else //for iOS 8
{
if ([mystring containsString: other])
{
//do something
}
}
答案 3 :(得分:0)
对于在 XLForm 中遇到此问题的用户,请确保在使用pod安装 XLForm
时
platform :ios, '7'
pod 'XLForm'
已在3.1
这
if ([cellClassString contains:@"/"]) {
}
到
if ([cellClassString rangeOfString:@"/"].location != NSNotFound) {
}
答案 4 :(得分:0)
我将我的解决方案封装在YJKit中,即使对于iOS 8以下的旧版本,也可以调用 - [NSString containsString:]。
bool _yj_streq(const char *str1, const char *str2, size_t length) {
for (int i = 0; i < length; i++) {
if (*str1++ != *str2++) {
return false;
}
}
return true;
}
- (BOOL)yj_containsString:(NSString *)string {
NSAssert(string != nil, @"*** -[%@ containsString:] can not use nil argument.", [self class]);
size_t len1 = (size_t)self.length;
size_t len2 = (size_t)string.length;
if (len1 == 0 || len2 == 0 || len1 < len2) {
return NO;
}
const char *str1 = self.UTF8String;
const char *str2 = string.UTF8String;
for (size_t i = 0; i <= len1 - len2; i++) {
const char *substr1 = str1 + i;
if (_yj_streq(substr1, str2, len2)) {
return YES;
} else {
continue;
}
}
return NO;
}
答案 5 :(得分:-1)
w0mbat给出的答案的快速版本:
extension NSString {
func compatibleContainsString(string: NSString) -> Bool{
let range = self.rangeOfString(string as String)
return range.length != 0
}
}