How to make buffer empty

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3.50/5 (2 votes)

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Hi,

I am using list int as buffer in my program

I need to check a condition after that I need to make buffer empty

C#

if (buffer1.Count != 0)
{
    int largestVal = buffer1[0];
    foreach (int temp in buffer1)
    {
       if (temp > largestVal)
         largestVal = temp;
       f2 = largestVal;
    }

    for (int z = f2 + 1; z < k - 1; z++)
    {
        if ((CANMsgIdList[i].MsgId == CANMsgIdList[z].MsgId))
        {
            buffer2[q2] = z;
        }
    }
 }
 //buffer1 = null;

The whole code is running in a for loop.
I am getting null exception at the line (buffer1.Count != 0)
Error: Object reference not set to an instance of an object.

Posted 7-Jan-14 3:22am

Member 10408451

Updated 7-Jan-14 3:27am

bowlturner

v2

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CPallini · Accepted Answer · 2014-01-07T03:31:00

Solution 3

If buffer1 is a List<int> </int>you have to call buffer1.Clear() in order to empty it.

Posted 7-Jan-14 3:31am

CPallini

OriginalGriff · Accepted Answer · 2014-01-07T03:29:00

Solution 1

If you are getting a null reference error on the line:

C#

if (buffer1.Count != 0)

Then the only possible reason is that butter1 is null: i.e. you have not assigned a value to it anywhere. Try looking at all the references to it, and look for either places where you assign buffer1 (and the assigned value could be null) or for somewhere in the code where you should be writing something like:

C#

buffer1 = new List<int>();

but aren't!

Posted 7-Jan-14 3:29am

OriginalGriff

Comments

bowlturner 7-Jan-14 9:34am

I had missed the List. I saw your answer, reread the problem and deleted mine when I saw my mistake.

OriginalGriff 7-Jan-14 9:43am

:thumbsup:
No problem - we all do it from time to time!