foreach statement cannot operate on variables of type 'object'
This question already has an answer here:
If you do not know the exact type of object, but you know for sure that whatever it is, it will have GetEnumerator on it (say, because it's a collection or one of your own objects that implements IEnumerable ) you can stop the compiler from issuing an error by casting to dynamic , like this:
foreach (var item in (dynamic)(ddlOther.DataSource)) {
...
}
The trade-of here is that if it turns out that ddlOther.DataSource does not have GetEnumerator , you will get an error at runtime, rather than a compile-time error.
Modify your code to check on the IEnumerable interface. It have the feeling underlying correction is more what you want.
public void DataSource(object source, object select, string Value = "UId", string Text = "Text")
{
ddlThis.DataSource = source;
ddlThis.DataTextField = Text;
ddlThis.DataValueField = Value;
ddlThis.DataBind();
ddlThisHidden.DataSource = source;
ddlThisHidden.DataTextField = Text;
ddlThisHidden.DataValueField = Value;
ddlThisHidden.DataBind();
if (select != null)
{
ddlOther.DataSource = select;
ddlOther.DataTextField = Text;
ddlOther.DataValueField = Value;
ddlOther.DataBind();
if (select is IEnumerable) //check if the object is a list of objects
foreach (var item in (IEnumerable)ddlOther.DataSource)
ddlThis.Items.Remove(item);
else //try to remove the single object
ddlThis.Items.Remove(select)
}
}
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