how to assignee each value to correspoding key in a generic way

Hi all

**--my problem is that i get key and value .but i have to save in the data base 
in a generic ways.My code is like this:-

local_keys = @params.keys
 first_addition = true
 param_value =0
 sql=String.new
  sql_value=String.new
 for key in 0...local_keys.length
 list=key.methods
       key_name = local_keys[key]
       value =  @params[key_name]
        puts "key "key_name.to_s " value "+value.to_s 
         if key_name!="action" && key_name!="controller" 
         @test_runs = TestRuns.new
            @test_run.ks=value(it is successful)(here ks is my column name)
but i want to save in a generic ways.
like  
         @test_runs.key_name= value.(it is not working )

can i do it in a generic way.if anybody knows please help me in this regard.but any how i got all the keys and values .only my problem is how i assignn each key to value.it should be in genric way.i have search it but i do not get the right way.

Try @test_runs.instance_variable_set("@#{key_name}", value)