Question

我有一个VB项目，我试图使用一些VBA代码，根据Excel工作表的第一列找到重复的行，并创建一个＆＃34; 1＆＃34;的标志，但是当VBA代码时在VB中使用会给出错误：

InvalidCastException未处理重载决议失败，因为没有Public＆＃39;＆lt;＆gt;＆＃39;可以使用以下参数调用：＆＃39;公共共享运算符＆lt;＆gt;（as As String，b As String）As Boolean＆＃39;：参数匹配参数＆＃39; a＆＃39;无法转换为＆＃39; __ ComObject＆＃39;到＆＃39; String＆＃39;。

- (void)viewDidLoad {

[self drawText];
[super viewDidLoad];

AppDelegate *appDelegate = (AppDelegate*)[[UIApplication sharedApplication] delegate];
NSFetchRequest *request = [[NSFetchRequest alloc]init];
NSEntityDescription *entity = [NSEntityDescription entityForName:@"Guest" inManagedObjectContext:appDelegate.managedObjectContext];
[request setEntity:entity];

NSManagedObjectContext *context = [appDelegate managedObjectContext];
NSError *error;
NSArray *fetchedObjects = [context executeFetchRequest:request error:&error];
NSString*guestString =@"";

for(NSManagedObject *obj in fetchedObjects) {

    guestString =[guestString stringByAppendingString:[NSString stringWithFormat:@"%@ %@ %@\n",[obj valueForKey:@"guestLastName" ],[obj valueForKey:@"guestName"],[obj valueForKey:@"guestZipCode"];
}

self.textView.text = guestString;
for(NSManagedObject *obj in fetchedObjects)
{
    NSLog(@"Name:%@\n Last Name %@\n" , [obj valueForKey:@"guestName"],[obj valueForKey:@"guestLastName"]);
   }  
}

任何帮助都会非常理解为什么会出现这种错误

Answer 1

当单元格为空时，调用MainSheet1.Cells（Duplicate_ID，1）给出Nothing（null）。因此，不要将其与字符串匹配，请将其检查为空值。

If MainSheet1.Cells(Duplicate_ID, 1) IsNot Nothing Then

End If

Answer 2

使用IsNot代替<>

            If Duplicate_ID IsNot Duplicate_Found_Index Then 'if the match index is not equals to current row number, then it is a duplicate value
                MainSheet1.Cells(Duplicate_ID, 34) = "1" 
            Else
                MainSheet1.Cells(Duplicate_ID, 34) = "0" 
            End If

Visual Basic If Then error

2 个答案: