I have a stored procedure with a decimal parameter .

how can send the decimal value?
I try this but it gives an error , invalid cast specified.

Dim p1 As SqlParameter = .Parameters.Add("@EstConstructionCost_10",
System.Data.SqlDbType.Decimal, 9).Value = CDbl(txtEstConstructionCost.Text)

' Dim p1 As SqlParameter = .Parameters.Add("@EstConstructionCost_10",
System.Data.SqlDbType.Decimal).Value = 10

p1.Precision = 10

p1.Scale = 0
I appreciate any help