iOS搜索框searchBarSearchButtonClick

如果同时设置了UISearchBarDelegate和UITextFieldDelegate，并且设置的允许输入的字符串，则需要在下面方法中，允许\n输入。

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string

完整代码

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string{    

if ([StringUtil isInputRuleNotBlank:string] || [string isEqualToString:@""] || [string isEqualToString:@"\n"]) {

//当输入符合规则和退格键时允许改变输入框        

return YES;    

}

else {      

  return NO;  

} }