Convert IEnumerable to DataTable

Zyphrax picture Zyphrax · Aug 10, 2009 · Viewed 112.2k times · Source

Is there a nice way to convert an IEnumerable to a DataTable?

I could use reflection to get the properties and the values, but that seems a bit inefficient, is there something build-in?

(I know the examples like: ObtainDataTableFromIEnumerable)

EDIT:
This question notified me of a problem handling null values.
The code I wrote below handles the null values properly.

public static DataTable ToDataTable<T>(this IEnumerable<T> items) {  
    // Create the result table, and gather all properties of a T        
    DataTable table = new DataTable(typeof(T).Name); 
    PropertyInfo[] props = typeof(T).GetProperties(BindingFlags.Public | BindingFlags.Instance);  

    // Add the properties as columns to the datatable
    foreach (var prop in props) { 
        Type propType = prop.PropertyType; 

        // Is it a nullable type? Get the underlying type 
        if (propType.IsGenericType && propType.GetGenericTypeDefinition().Equals(typeof(Nullable<>))) 
            propType = new NullableConverter(propType).UnderlyingType;  

        table.Columns.Add(prop.Name, propType); 
    }  

    // Add the property values per T as rows to the datatable
    foreach (var item in items) {  
        var values = new object[props.Length];  
        for (var i = 0; i < props.Length; i++) 
            values[i] = props[i].GetValue(item, null);   

        table.Rows.Add(values);  
    } 

    return table; 
} 

Answer

CD.. picture CD.. · Aug 10, 2009

Look at this one: Convert List/IEnumerable to DataTable/DataView

In my code I changed it into a extension method:

public static DataTable ToDataTable<T>(this List<T> items)
{
    var tb = new DataTable(typeof(T).Name);

    PropertyInfo[] props = typeof(T).GetProperties(BindingFlags.Public | BindingFlags.Instance);

    foreach(var prop in props)
    {
        tb.Columns.Add(prop.Name, prop.PropertyType);
    }

     foreach (var item in items)
    {
       var values = new object[props.Length];
        for (var i=0; i<props.Length; i++)
        {
            values[i] = props[i].GetValue(item, null);
        }

        tb.Rows.Add(values);
    }

    return tb;
}