[dba-SQLServer]Internationalization problem

Dear group,

is there any reliable known algorithm to 'translate' numbers users type in a
user interface into valid SQL numbers?
I want to generate SQL statements that include number users type in. The
problem is, some of my users use non-american notation (, as decimal
separator and . as thousand separator). Therefore, all input is accepted as
a string and needs to be converted to valid SQL numbers with a . as decimal
separator.

TIA,

Michael