Datatable

13y2.2kLearn iOS Programming

hello how to combine below given datatable rows by id .like below:

ID | NAME | SURNAME |

--------------------------------

1 | null | MIKE

-------------------------------

1 | JON | null

-------------------------

2 | SON | null

----------------------

2 | null | Berry

RESULT WILL BE AS BELOW

ID | NAME | SURNAME |

--------------------------------

1 | JON | MIKE

-------------------------------

2 | SON | Berry

Thanks in advance

8 Replies

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Vulpes13y ago
Accepted answer
Suppose we can assume that lines with the same ID are next to each other in the Rows Collection, that there are exactly two of them and that there no inconsistencies in the non-null columns (or, if there are, then the first line will always 'win').

The following code should then combine the lines:

for(int i = dt.Rows.Count - 1; i >= 0; i -= 2)
{
for(int j = 1; j < dt.Columns.Count; j++)
{
if (Convert.IsDBNull(dt.Rows[i - 1][j]) || dt.Rows[i - 1][j] == null)
{
dt.Rows[i - 1][j] = dt.Rows[i][j];
}
}
dt.Rows.RemoveAt(i);
}
13y ago
Thanks Vulpes.
13y ago
Sorry, but the answer You asked attend me to ask help from forum.
Thanks
Vulpes13y ago
Well, as I intimated in my earlier post, to do this more generally is much more complicated and you need to know what, if anything, it's safe to assume.

For example, can you be sure that the lines which need combining will always be next to each other, could there be more than 2 lines with the same ID column and what should you do if lines with the same ID have non-null columns which don't have the same values.
13y ago
Hi,

in the table rows like this.And a lot of.Will change.So I need to create something dynamical.To combine this row based on ID in one table.
Thanks
13y ago
But that is not dynamically.There may be lots of rows, columns.
Vulpes13y ago
As those lines stand, you could do it like this where 'dt' is your datatable:

dt.Rows[0]["NAME"] = dt.Rows[1]["NAME"];
dt.Rows[2]["SURNAME"] = dt.Rows[3]["SURNAME"];
dt.Rows.RemoveAt(3);
dt.Rows.RemoveAt(1);

However, if you had a sequence of pairs of lines such as this and you didn't know in advance which columns would be null, the code would be more complicated.
Gaurav Gupta13y ago
Is it only one table?