List of Dates ordered in a certain way

I have a list of dates (strings in the format yyyyMM) as follows:

I'd like to reorder them to be as follows:

I thought I could reverse the strings (i.e. 016102) to order them but obviously with a month >= 10 it causes issues resulting in the list coming out like:

I tried the following:
MyList.OrderBy(n => string.Concat(n.datestring.Reverse())).Select(n => n);

Is there a nice succinct way of doing this (LINQ would be nice)? Thanks for any help.

edited Nov 21 '18 at 20:20

asked Nov 21 '18 at 20:18

scgough

3,01121632

You don't want to reverse the strings, you want to slice it into two substrings, year and month and then order by those separately (month, then year). Try something like myList.OrderBy(s => s.Substring(4)).ThenBy(s => s.Substring(0, 4))

– Brian Rogers
Nov 21 '18 at 20:22

2

So, to be clear, you want them ordered by month and then by year? Or, do you just want them in the order that you say. Consider keep date-ish and time-ish things as either DateTimes or TimeSpans. They are much easier to handle. However, @BrianRogers' solution is probably the way to go (assuming that I've correctly guessed your problem statement)

– Flydog57
Nov 21 '18 at 20:26

Yes that’s the ticket Brian. It’s late. I had a brain fart! Thanks for unsticking me! I’ll give that a go.

– scgough
Nov 21 '18 at 20:28

add a comment |

I have a list of dates (strings in the format yyyyMM) as follows:

I'd like to reorder them to be as follows:

I thought I could reverse the strings (i.e. 016102) to order them but obviously with a month >= 10 it causes issues resulting in the list coming out like:

I tried the following:
MyList.OrderBy(n => string.Concat(n.datestring.Reverse())).Select(n => n);

Is there a nice succinct way of doing this (LINQ would be nice)? Thanks for any help.

edited Nov 21 '18 at 20:20

asked Nov 21 '18 at 20:18

scgough

3,01121632

You don't want to reverse the strings, you want to slice it into two substrings, year and month and then order by those separately (month, then year). Try something like myList.OrderBy(s => s.Substring(4)).ThenBy(s => s.Substring(0, 4))

– Brian Rogers
Nov 21 '18 at 20:22

2

So, to be clear, you want them ordered by month and then by year? Or, do you just want them in the order that you say. Consider keep date-ish and time-ish things as either DateTimes or TimeSpans. They are much easier to handle. However, @BrianRogers' solution is probably the way to go (assuming that I've correctly guessed your problem statement)

– Flydog57
Nov 21 '18 at 20:26

Yes that’s the ticket Brian. It’s late. I had a brain fart! Thanks for unsticking me! I’ll give that a go.

– scgough
Nov 21 '18 at 20:28

add a comment |

I have a list of dates (strings in the format yyyyMM) as follows:

I'd like to reorder them to be as follows:

I thought I could reverse the strings (i.e. 016102) to order them but obviously with a month >= 10 it causes issues resulting in the list coming out like:

I tried the following:
MyList.OrderBy(n => string.Concat(n.datestring.Reverse())).Select(n => n);

Is there a nice succinct way of doing this (LINQ would be nice)? Thanks for any help.

edited Nov 21 '18 at 20:20

asked Nov 21 '18 at 20:18

scgough

3,01121632

I have a list of dates (strings in the format yyyyMM) as follows:

I'd like to reorder them to be as follows:

I thought I could reverse the strings (i.e. 016102) to order them but obviously with a month >= 10 it causes issues resulting in the list coming out like:

I tried the following:
MyList.OrderBy(n => string.Concat(n.datestring.Reverse())).Select(n => n);

Is there a nice succinct way of doing this (LINQ would be nice)? Thanks for any help.

c# linq sorting

edited Nov 21 '18 at 20:20

asked Nov 21 '18 at 20:18

scgough

3,01121632

edited Nov 21 '18 at 20:20

asked Nov 21 '18 at 20:18

scgough

3,01121632

edited Nov 21 '18 at 20:20

asked Nov 21 '18 at 20:18

scgough

3,01121632

asked Nov 21 '18 at 20:18

scgough

3,01121632

asked Nov 21 '18 at 20:18

scgough

3,01121632

You don't want to reverse the strings, you want to slice it into two substrings, year and month and then order by those separately (month, then year). Try something like myList.OrderBy(s => s.Substring(4)).ThenBy(s => s.Substring(0, 4))

– Brian Rogers
Nov 21 '18 at 20:22

2

So, to be clear, you want them ordered by month and then by year? Or, do you just want them in the order that you say. Consider keep date-ish and time-ish things as either DateTimes or TimeSpans. They are much easier to handle. However, @BrianRogers' solution is probably the way to go (assuming that I've correctly guessed your problem statement)

– Flydog57
Nov 21 '18 at 20:26

Yes that’s the ticket Brian. It’s late. I had a brain fart! Thanks for unsticking me! I’ll give that a go.

– scgough
Nov 21 '18 at 20:28

add a comment |

You don't want to reverse the strings, you want to slice it into two substrings, year and month and then order by those separately (month, then year). Try something like myList.OrderBy(s => s.Substring(4)).ThenBy(s => s.Substring(0, 4))

– Brian Rogers
Nov 21 '18 at 20:22

2

So, to be clear, you want them ordered by month and then by year? Or, do you just want them in the order that you say. Consider keep date-ish and time-ish things as either DateTimes or TimeSpans. They are much easier to handle. However, @BrianRogers' solution is probably the way to go (assuming that I've correctly guessed your problem statement)

– Flydog57
Nov 21 '18 at 20:26

Yes that’s the ticket Brian. It’s late. I had a brain fart! Thanks for unsticking me! I’ll give that a go.

– scgough
Nov 21 '18 at 20:28

You don't want to reverse the strings, you want to slice it into two substrings, year and month and then order by those separately (month, then year). Try something like myList.OrderBy(s => s.Substring(4)).ThenBy(s => s.Substring(0, 4))

– Brian Rogers
Nov 21 '18 at 20:22

So, to be clear, you want them ordered by month and then by year? Or, do you just want them in the order that you say. Consider keep date-ish and time-ish things as either DateTimes or TimeSpans. They are much easier to handle. However, @BrianRogers' solution is probably the way to go (assuming that I've correctly guessed your problem statement)

– Flydog57
Nov 21 '18 at 20:26

Yes that’s the ticket Brian. It’s late. I had a brain fart! Thanks for unsticking me! I’ll give that a go.

– scgough
Nov 21 '18 at 20:28

add a comment |

2 Answers
2

active

oldest

votes

Using LINQ, you order by the two digit month then the year (and month, but that shouldn't matter):

var ans = src.OrderBy(s => s.Substring(4)).ThenBy(s => s);

answered Nov 21 '18 at 20:24

NetMage

13.6k12035

You beat me to it! This should work fine.

– Elemental Pete
Nov 21 '18 at 20:26

Nice one. Thank you!

– scgough
Nov 21 '18 at 20:29

add a comment |

I'd cheat and order by dates personally, via an Extension Method:

New class:

public static class DateOperations

{

    public static List<DateTime> GetDates(this List<string> dateStrings)

    {

        List<DateTime> asDates = new List<DateTime>();

        dateStrings.ForEach(e =>

        asDates.Add(DateTime.ParseExact(e, "yyyyMM", CultureInfo.InvariantCulture, DateTimeStyles.None))

        );



        return asDates;

    }

}

And then:

var ordered = myList.GetDates().OrderBy(ord => ord.Month).ThenBy(then => then.Year);

And then when I needed the string again I'd use:

date[_whateverAccessorReally].ToString("yyyyMM");

answered Nov 21 '18 at 21:02

Austin T French

2,50011429

add a comment |

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2 Answers
2

active

oldest

votes

2 Answers
2

active

oldest

votes

Using LINQ, you order by the two digit month then the year (and month, but that shouldn't matter):

var ans = src.OrderBy(s => s.Substring(4)).ThenBy(s => s);

answered Nov 21 '18 at 20:24

NetMage

13.6k12035

You beat me to it! This should work fine.

– Elemental Pete
Nov 21 '18 at 20:26

Nice one. Thank you!

– scgough
Nov 21 '18 at 20:29

add a comment |

Using LINQ, you order by the two digit month then the year (and month, but that shouldn't matter):

var ans = src.OrderBy(s => s.Substring(4)).ThenBy(s => s);

answered Nov 21 '18 at 20:24

NetMage

13.6k12035

You beat me to it! This should work fine.

– Elemental Pete
Nov 21 '18 at 20:26

Nice one. Thank you!

– scgough
Nov 21 '18 at 20:29

add a comment |

Using LINQ, you order by the two digit month then the year (and month, but that shouldn't matter):

var ans = src.OrderBy(s => s.Substring(4)).ThenBy(s => s);

answered Nov 21 '18 at 20:24

NetMage

13.6k12035

Using LINQ, you order by the two digit month then the year (and month, but that shouldn't matter):

var ans = src.OrderBy(s => s.Substring(4)).ThenBy(s => s);

answered Nov 21 '18 at 20:24

NetMage

13.6k12035

answered Nov 21 '18 at 20:24

NetMage

13.6k12035

answered Nov 21 '18 at 20:24

NetMage

13.6k12035

answered Nov 21 '18 at 20:24

NetMage

13.6k12035

You beat me to it! This should work fine.

– Elemental Pete
Nov 21 '18 at 20:26

Nice one. Thank you!

– scgough
Nov 21 '18 at 20:29

add a comment |

You beat me to it! This should work fine.

– Elemental Pete
Nov 21 '18 at 20:26

Nice one. Thank you!

– scgough
Nov 21 '18 at 20:29

You beat me to it! This should work fine.

– Elemental Pete
Nov 21 '18 at 20:26

Nice one. Thank you!

– scgough
Nov 21 '18 at 20:29

add a comment |

I'd cheat and order by dates personally, via an Extension Method:

New class:

public static class DateOperations

{

    public static List<DateTime> GetDates(this List<string> dateStrings)

    {

        List<DateTime> asDates = new List<DateTime>();

        dateStrings.ForEach(e =>

        asDates.Add(DateTime.ParseExact(e, "yyyyMM", CultureInfo.InvariantCulture, DateTimeStyles.None))

        );



        return asDates;

    }

}

And then:

var ordered = myList.GetDates().OrderBy(ord => ord.Month).ThenBy(then => then.Year);

And then when I needed the string again I'd use:

date[_whateverAccessorReally].ToString("yyyyMM");

answered Nov 21 '18 at 21:02

Austin T French

2,50011429

add a comment |

I'd cheat and order by dates personally, via an Extension Method:

New class:

public static class DateOperations

{

    public static List<DateTime> GetDates(this List<string> dateStrings)

    {

        List<DateTime> asDates = new List<DateTime>();

        dateStrings.ForEach(e =>

        asDates.Add(DateTime.ParseExact(e, "yyyyMM", CultureInfo.InvariantCulture, DateTimeStyles.None))

        );



        return asDates;

    }

}

And then:

var ordered = myList.GetDates().OrderBy(ord => ord.Month).ThenBy(then => then.Year);

And then when I needed the string again I'd use:

date[_whateverAccessorReally].ToString("yyyyMM");

answered Nov 21 '18 at 21:02

Austin T French

2,50011429

add a comment |

I'd cheat and order by dates personally, via an Extension Method:

New class:

public static class DateOperations

{

    public static List<DateTime> GetDates(this List<string> dateStrings)

    {

        List<DateTime> asDates = new List<DateTime>();

        dateStrings.ForEach(e =>

        asDates.Add(DateTime.ParseExact(e, "yyyyMM", CultureInfo.InvariantCulture, DateTimeStyles.None))

        );



        return asDates;

    }

}

And then:

var ordered = myList.GetDates().OrderBy(ord => ord.Month).ThenBy(then => then.Year);

And then when I needed the string again I'd use:

date[_whateverAccessorReally].ToString("yyyyMM");

answered Nov 21 '18 at 21:02

Austin T French

2,50011429

I'd cheat and order by dates personally, via an Extension Method:

New class:

public static class DateOperations

{

    public static List<DateTime> GetDates(this List<string> dateStrings)

    {

        List<DateTime> asDates = new List<DateTime>();

        dateStrings.ForEach(e =>

        asDates.Add(DateTime.ParseExact(e, "yyyyMM", CultureInfo.InvariantCulture, DateTimeStyles.None))

        );



        return asDates;

    }

}

And then:

var ordered = myList.GetDates().OrderBy(ord => ord.Month).ThenBy(then => then.Year);

And then when I needed the string again I'd use:

date[_whateverAccessorReally].ToString("yyyyMM");

answered Nov 21 '18 at 21:02

Austin T French

2,50011429

answered Nov 21 '18 at 21:02

Austin T French

2,50011429

answered Nov 21 '18 at 21:02

Austin T French

2,50011429

answered Nov 21 '18 at 21:02

Austin T French

2,50011429

add a comment |

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