c# - How to convert Enumerable value to right format? -


i have following code:

client data = this.controllerpacients.getbyid(id).asenumerable()                 .select(row => new client                            {                               taxcode = convert.toint32(row.field<int>("taxcode")).tostring()                             })                .single();

so, in database field taxcode integer. in model client string.

i error in line, when try convert types:

system.invalidcastexception: 'specified cast not valid.'

attachment:

enter image description here

i tried way also:

datatable data =  db.getdatatable("select * table id =4");   var c = data.rows[0].field<int>("taxcode");

i have reply question inappropriate answer... i'm going break question down , explain why it's horrible question...

in code:

client data = this.controllerpacients.getbyid(id).asenumerable()                 .select(row => new client                            {                               taxcode = convert.toint32(row.field<int>("taxcode")).tostring()                             })                .single();

... fail explain of it. here points:

a) controllerpacients you've spelled incorrectly way, class-level property hiding cast within it, meaning we'd never able see bug here on stack overflow. should provide entire code, or fill in gaps explanation.

b) getbyid(id) returns array-like type, can't see is. using anenumerable in situation has serious code-smell. isn't there way can select directly getbyid result, or access appears row collection via property of getbyid result?

c) 25 thousand casts... if field int , class has string, use .tostring() don't need conversion going on.

d) should consider creating method on client class takes patient parameter , loads it's values that, rather loading original patient's datasource. example client.loadtaxcodefrompatient(patient)

e) you're having put single() call @ end of shouldn't collection anyway, if getbyid returns other patient class it's doing wrong.

sorry beating question that, gotta :)


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