I have got:
string [] total_content;

I am appending to it data on every iteration.

total_content ~= somedata

File file = File(`D:\code\2vlad\result.txt`, "a+");
file.write(total_content);

I need to write it's to file by lines. Like:
somedataline1
somedataline2
somedataline3

I tried to do like:
total_content ~= somedata ~ "\n"

but in result I am getting all data in one line:
somedataline1 "\n" somedataline2 "\n" somedataline3 "\n"

what I am doing wrong? I know about split, but how it can be called on writing time?

On Tuesday, 15 March 2016 at 10:58:16 UTC, Suliman wrote:
> I have got:
> string [] total_content;
>
> I am appending to it data on every iteration.
>
> total_content ~= somedata
>
> File file = File(`D:\code\2vlad\result.txt`, "a+");
> file.write(total_content);
>
> I need to write it's to file by lines. Like:
> somedataline1
> somedataline2
> somedataline3
>
> I tried to do like:
> total_content ~= somedata ~ "\n"
>
> but in result I am getting all data in one line:
> somedataline1 "\n" somedataline2 "\n" somedataline3 "\n"
>
> what I am doing wrong? I know about split, but how it can be called on writing time?

Windows CRLF line endings, perhaps?

On Tuesday, 15 March 2016 at 10:58:16 UTC, Suliman wrote:
> I have got:
> string [] total_content;
>
> I am appending to it data on every iteration.
>
> total_content ~= somedata
>
> File file = File(`D:\code\2vlad\result.txt`, "a+");
> file.write(total_content);
>
> I need to write it's to file by lines. Like:
> somedataline1
> somedataline2
> somedataline3
>
> I tried to do like:
> total_content ~= somedata ~ "\n"
>
> but in result I am getting all data in one line:
> somedataline1 "\n" somedataline2 "\n" somedataline3 "\n"
>
> what I am doing wrong? I know about split, but how it can be called on writing time?

You're on windows, is newline not '\r\n' ? (I'm guessing here!)

I created better example to show.

string [] myarr = ["foo", "bar", "baz"];
myarr ~= "new";
File file = File(`result.txt`, "w");
file.write(myarr);

is any way to write myarr to file in byLine mode

On Tuesday, 15 March 2016 at 12:55:17 UTC, Suliman wrote:
> I created better example to show.
>
> string [] myarr = ["foo", "bar", "baz"];
> myarr ~= "new";
> File file = File(`result.txt`, "w");
> file.write(myarr);
>
> is any way to write myarr to file in byLine mode

myarr
   .each!(line => file.writeln(line));

On Tuesday, 15 March 2016 at 12:55:17 UTC, Suliman wrote:
> I created better example to show.
>
> string [] myarr = ["foo", "bar", "baz"];
> myarr ~= "new";
> File file = File(`result.txt`, "w");
> file.write(myarr);
>
> is any way to write myarr to file in byLine mode

 void main(){
     import std.stdio;
     import std.ascii;
     import std.algorithm;

     string[] myArr = ["foo", "bar", "baz"];
     myArr ~= "new";
     writeln("=== each! ===");
     myArr.each!(a => writeln(a));
     writeln("=== Using format ===");
     writefln("%-(%s\n%)", myArr);

     writeln("=== Using joiner ===");
     myArr.joiner(std.ascii.newline).writeln;
 }


Output:
=== each! ===
foo
bar
baz
new
=== Using format ===
foo
bar
baz
new
=== Using joiner ===
foo
bar
baz
new

On Tuesday, 15 March 2016 at 10:58:16 UTC, Suliman wrote:
> I have got:
> string [] total_content;
>
> I am appending to it data on every iteration.
>
> total_content ~= somedata
>
> File file = File(`D:\code\2vlad\result.txt`, "a+");
> file.write(total_content);
>
> I need to write it's to file by lines. Like:
> somedataline1
> somedataline2
> somedataline3
>
> I tried to do like:
> total_content ~= somedata ~ "\n"
>
> but in result I am getting all data in one line:
> somedataline1 "\n" somedataline2 "\n" somedataline3 "\n"
>
> what I am doing wrong? I know about split, but how it can be called on writing time?

http://forum.dlang.org/group/learn would be more appropriate for this sort of question.