SqlParameter数组到对象

Question

SqlParameter[] _parameters = {                
     new SqlParameter( "@IDNumber", Person.IDNumber ),
     new SqlParameter( "@Name", Person.Name ),
     new SqlParameter( "@Surname", Person.Surname )
};

How to get the "Name" value from object array without using index? What I want to do is,

oPerson.Name = _parameters.Find(@Name).Value;

Answer 1

Use the following:

_parameters.Single(p => p.ParameterName == "@Name").Value;

This assumes one and only one instance of a SqlParameter with a given ParameterName exists. If you're unsure if one exists, do the following:

var param = _parameters.SingleOrDefault(p => p.ParameterName == "@Name");
if (param != null) { oPerson.Name = param.Value; }

Answer 2

Using Linq, it is easy

string pName = "@Name";
var p = _parameters.FirstOrDefault(x => x.ParameterName == pName);
if(p != null) 
    oPerson.Name = p.Value.ToString();

I assume that you need this code because you are unsure about the presence or not of your parameter. So using FirstOrDefault allows to test for the result without using directly the Value property if your parameter doesn't exists in the collection

Answer 3

您可以使用First方法并通过其Name获取参数。

oPerson.Name = _parameters.First(x => x.ParameterName == "@Name").Value;

Answer 4

You could use Linq like in

oPerson.Name = _parameters.First( param => param.ParameterName.Equals("@Name")).Value;

to search for the value of "@Name" again.