iterate through particular column in a datatable

Question

I am Working in asp.net and c#.

I have a datatable in my application with one column.I want to iterate through that column values and check those values with someother value.please tell me how to do that.I tried it with foreach but its not working.

Code:

  foreach (DataRow dr in dt.Rows)
        {
            int code = Convert.ToInt32(dt.Rows[0]["Code"]);

            if (code == pcode)
            {
                //do something
            }
            else 
            { }
        }

Note:

dt is my datatable with column code.I want to compare all values in column code with pcode.

You have showed a way, what's wrong with it, what do you actually need? — Tim Schmelter, Jan 21 '13 at 08:23
**Never** use _"not working"_ on SO! Instead try to explain the wrong behaviour, bug or exception with meaningful words. — Tim Schmelter, Jan 21 '13 at 08:28

score 2 · Accepted Answer · answered Jan 21 '13 at 08:24

2

int code = Convert.ToInt32(dr["Code"]);

Although you might want to check for NULL also :)

answered Jan 21 '13 at 08:24

Paul Alan Taylor

10,474
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score 1 · Answer 2 · answered Jan 21 '13 at 08:23

1

Inside your loop, access dr, instead of dt.Rows[0].

answered Jan 21 '13 at 08:23

Oskar Berggren

5,583
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score 0 · Answer 3 · answered Jan 21 '13 at 08:25

You are always accessing the first row:

dt.Rows[0]["Code"]  // use dr instead of dt.Rows[0]

dt is my datatable with column code.I want to compare all values in column code with pcode.

So am i right when i assume that you want to compare all values with one variable, if all fields equal this value, a bool variable should be true, otherwise false?

You can use Linq:

var allEqual = dt.AsEnumerable()
                 .All(r => r.Field<int>("Code") == pcode);

Enumerable.All determines whether all elements of a sequence satisfy a condition.

score 0 · Answer 4 · answered Jan 21 '13 at 08:30

foreach (DataRow dr in dt.Rows)
{
    object o = dr["Code"];
    if (o != DBNull.Value) // Check for null
    {
        int code = Convert.ToInt32(o);

        if (code == pcode)
        {
            //do something
        }
        else 
        { }
    }
}

iterate through particular column in a datatable

4 Answers4

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