Cannot assign <null> to an implicitly-typed local variable

Question

I want to to select a field from Data table dt_branches_global in such a way that, if radioButton_QP is Checked then the Data table will contain a string field otherwise the Data Table contain an int field. This is what I am doing. But I am getting error while initializing the variable Var.

var AllBranch_IDs = null;

if (radioButton_QP.Checked == true)   
AllBranch_IDs = dt_branches_global.AsEnumerable().Select(x => x.Field<string>("BusinessSectorID")).ToArray();
else

AllBranch_IDs = dt_branches_global.AsEnumerable().Select(x => x.Field<int>("BusinessSectorID")).ToArray();

Answer 1

The compiler is still strongly typed so it needs to figure out the type. It is impossible for the compiler to infer the type of you assign it to null. Then you later on try to assign it to two different types. An array of ints and an array of strings.

Try something like:

string[] AllBranch_IDs = null;

if (radioButton_QP.Checked == true)   
AllBranch_IDs = dt_branches_global.AsEnumerable().Select(x => x.Field<string>("BusinessSectorID")).ToArray();
else

AllBranch_IDs = dt_branches_global.AsEnumerable().Select(x => x.Field<int>("BusinessSectorID").ToString()).ToArray();