WPF如何将相同的事件Lambda表达式分配给两个不同的元素

Question

I have two datagrids with same properties defined in code behind.

var dtg = new DataGrid();

then I assign an event though lambda expression (quite a long one):

dtg.LoadingRow += (object sender, DataGridRowEventArgs e) =>
{
    ...
};

which I do not want to replicate. So how can I do that (pseudocode):

var dtg2 = new DataGrid();
dtg2.LoadingRow = dtg.LoadingRow;

thanx

Answer 1

simply assign your lambda to variable:

EventHandler<DataGridRowEventArgs> handler =  (object sender, DataGridRowEventArgs e) =>
{
    ...
};
var dtg2 = new DataGrid();
dtg2.LoadingRow += handler;

Or, better, name your handler - make it to an ordinary method in your class and use its name.

Answer 2

Why don't you just replace the lambda expression with an event handler, ie a method?:

private void OnLoadingRow(object sender, DataGridRowEventArgs e)
{
    //....
}

You could then use the same event handler for several DataGrid's:

dtg.LoadingRow += OnLoadingRow;
dtg2.LoadingRow += OnLoadingRow;

The other option is to define your entire lamda as a variable or field as suggested by @Rafal but I can't really see why this would be better than adding a method - at least in the general case.