Datatable - Get max(date) from string type column

Question

I have this datatable result in c#

DAY      Employee Job1   Job2   Job3
1/1/2012    a    1      1      1 
1/1/2012    b    2      2      2
1/1/2012    c    2      1      4
1/1/2012    d    4      2      1
1/2/2012    a    3      2      5
1/2/2012    b    2      2      2
1/2/2012    c    3      3      3
1/2/2012    d    1      1      1
1/3/2013    a    5      5      5
1/3/2013    b    2      2      6
1/3/2013    c    1      1      1
3/13/2013   d    2      3      4
2/1/2013    a    2      2      2
2/1/2013    b    5      5      2
2/7/2013    c    2      2      2
2/5/2013    a    3      3      3
3/2/2013    b    2      3      3
2/1/2013    a    4      4      2

Now i want to find the max date from the first column(MM/dd/yyyy) which should be 3/13/2013. Also note that this column is of string datatype.

Please, can anybody suggest me how to do this with "Linq" in c# or is there a simple way to do this?

Tim Schmelter · Accepted Answer · 2013-03-16T12:48:32.093

2

Use DateTime.Parse or DateTime.ParseExact to parse a string to a datatime. This should work:

DateTime maxDate = table.AsEnumerable()
    .Max(r => DateTime.Parse(r.Field<string>("DAY")));

However, why is it a string in the first place?

Edit You should also take the culture into account which was used to create this string. You have to use this culture again when you parse the string.

So this results works for different cultures but the result is different as you can see here:

System.Threading.Thread.CurrentThread.CurrentCulture = CultureInfo.CreateSpecificCulture("en-US");
DateTime maxDate = table.AsEnumerable()
    .Max(r => DateTime.Parse(r.Field<string>("DAY")));
Console.WriteLine(maxDate);
System.Threading.Thread.CurrentThread.CurrentCulture = CultureInfo.CreateSpecificCulture("de-DE"); // germany
maxDate = table.AsEnumerable()
    .Max(r => DateTime.Parse(r.Field<string>("DAY")));
Console.WriteLine(maxDate);

edited Mar 16 '13 at 12:48

answered Mar 16 '13 at 12:40

Tim Schmelter

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Wow Tim, you are a maestro!! Thank you, it works! I exported this data from an excel sheet and after export the datatable shows this column as string datatype. – user1254053 Mar 16 '13 at 12:51
Hi @tim what if a day fields comes as "4/1/2012" ? max date will be taking this – Praveen Prasannan May 24 '13 at 06:29
@Praveen: what date is that, first of April or fourth of January? Have you tried it? Actually I don't understand your question. – Tim Schmelter May 24 '13 at 06:41

score 0 · Answer 2 · edited May 23 '17 at 11:57

0

Formatting between programs can be annoying even if they are made by the same company. This thread is similar and hopefully will point you in the right direction:

DateTime format mismatch on importing from Excel Sheet

if you've confirmed it's a String, then have you tried a simple: DateTime dt = Convert.ToDateTime(date);?

edited May 23 '17 at 11:57

Community

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answered Mar 16 '13 at 12:08

Gander7

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Datatable - Get max(date) from string type column

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