You just need to set the dataformatstring with the way you want it to be populated.
As shown on the MSDN page:
Money:
<asp:BoundColumn HeaderText="Price" DataField="Price" DataFormatString="{0:c}" />
Using {0: c}, placing the number after the value of c (for example, {0: c2}) will give you many decimal places.
The date:
<asp:boundfield datafield="MyDate" dataformatstring="{0:MM/dd/yyyy}" />
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