问题
My project's codebase has a legacy method that takes a DataRow as a parameter for which I would like to create a unit test method.
How can I manually create a DataRow object to pass to the method? The System.Data.DataRow class doesn't have a public-facing constructor.
回答1:
A DataRow can be created by creating a new DataTable instance, adding columns to the DataTable corresponding to the "keys" that the DataRow needs to have, and then calling NewRow()
on the DataTable. For example:
DataTable usersTable = new DataTable();
usersTable.Columns.Add("FirstName");
usersTable.Columns.Add("LastName");
usersTable.Columns.Add("Email");
DataRow userRow = usersTable.NewRow();
userRow["FirstName"] = "Elmer";
userRow["LastName"] = "Example";
userRow["Email"] = "elmer@example.com";
回答2:
You should note that if the Unit Test needed to enforce type constraints on the DataColumnCollection
(Columns) for the DataTable
- you can use the overloaded constructor of the DataColumn
class to include the expected Type
.
var dt = new DataTable();
var dc = new DataColumn("Age", typeof(int));
dt.Columns.Add(dc);
var dr = dt.NewRow();
dr["Age"] = "test"; // throws an ArgumentException
//Input string was not in a correct format. Couldn't store<test> in Age Column. Expected type is Int32.
来源:https://stackoverflow.com/questions/44010345/how-can-i-manually-programmatically-create-a-datarow