How to flexibly use the select method in datatable

 

In operationDatatableYou may also encounter a common problem.DatatableSome rows in modify the status,
I mean manually explicitly modified, for exampleCode:

//Adds a Status column to the new table to indicate whether the table has been accessed.

Datatable temptable = dtdatatable [I]. Copy ();

Temptable. Columns. Add ("Visited",Typeof(Bool));

Foreach(Datarow temprowInTemptable. Rows)

{

Temprow ["Visited"] =False;

}

 

//Then, some rows are operated and the status is modified.

Foreach(Datarow adatarowInTemptable. Rows)

{

If(Adatarow ["Stepno"]. Tostring ())

{

Adatarow ["Totalprice"] = 0;

Adatarow ["Visited"] =True;

}

}

Then Temptable There will be some Row Column Visited = false . How to find these columns?

 

Of course it corresponds to the question in this article

Datarow [] unvisitedrows = temptable. Select ("Visited = false");

apparently, it returns a datarow , next, how to operate on each row in the array, needless to say. One thing to note is that my
previous blog

Dataset, datatable. datarowCopy Method--Solution: This row already belongs to another table.

 

In addition,PublicDatarow[] Select ( String Filterexpression)

Filterexpression   This parameter can also be used   And, or  And other operators, such:  Filterexpression 
="Id = 'D' or stepnt <> ''" .