/// <summary>
/// Indicates if the value of the specified column in the
/// <see cref="ExcelDataReader"/> is <see langword="null"/> or <see cref="String.Empty"/>.
/// </summary>
/// <param name="reader">
/// The input <see cref="ExcelDataReader"/>, which acts as the this
/// instance for the extension method.
/// </param>
/// <param name="columnIndex">The column index.</param>
/// <returns>
/// <see langword="true"/> if the value is <see langword="null"/> or
/// <see cref="String.Empty"/>; otherwise, <see langword="false"/>.
/// </returns>
public static bool IsNullOrWhiteSpace(this ExcelDataReader reader, int columnIndex)
{
if (!columnIndex.Between(0, reader.FieldCount))
{
return(true);
}
return(reader.IsNull(columnIndex) || String.IsNullOrWhiteSpace(reader[columnIndex].ToString()));
}
/// <summary>
/// Indicates if the value of the specified column in the
/// <see cref="ExcelDataReader"/> is <see langword="null"/> or <see cref="String.Empty"/>.
/// </summary>
/// <param name="reader">
/// The input <see cref="ExcelDataReader"/>, which acts as the this
/// instance for the extension method.
/// </param>
/// <param name="columnName">The column name.</param>
/// <returns>
/// <see langword="true"/> if the value is <see langword="null"/> or
/// <see cref="String.Empty"/>; otherwise, <see langword="false"/>.
/// </returns>
public static bool IsNullOrWhiteSpace(this ExcelDataReader reader, string columnName)
{
if (String.IsNullOrWhiteSpace(columnName) || !reader.FieldNames.Contains(columnName))
{
return(true);
}
return(reader.IsNull(columnName) || String.IsNullOrWhiteSpace(reader[columnName].ToString()));
}
/// <summary>
/// Indicates if the value of the specified column in the
/// <see cref="ExcelDataReader"/> is <see langword="null"/>.
/// </summary>
/// <param name="reader">
/// The input <see cref="ExcelDataReader"/>, which acts as the this
/// instance for the extension method.
/// </param>
/// <param name="columnIndex">The column index.</param>
/// <returns>
/// <see langword="true"/> if the value is <see langword="null"/>;
/// otherwise, <see langword="false"/>.
/// </returns>
public static bool IsNull(this ExcelDataReader reader, int columnIndex)
{
if (!columnIndex.Between(0, reader.FieldCount))
{
return(true);
}
return(reader[columnIndex] == null);
}
/// <summary>
/// Provides strongly-typed access to each of the column values in the <see cref="ExcelDataReader"/>.
/// </summary>
/// <typeparam name="T">The return type of the column.</typeparam>
/// <param name="reader">
/// The input <see cref="ExcelDataReader"/>, which acts as the this
/// instance for the extension method.
/// </param>
/// <param name="columnName">The column name.</param>
/// <returns>
/// The value, of type <typeparamref name="T"/>, of the column specified
/// by <paramref name="columnName"/>.
/// </returns>
public static T Field <T>(this ExcelDataReader reader, string columnName)
{
T fieldValue;
try
{
fieldValue = UnboxT <T> .Unbox(reader[columnName]);
}
catch (InvalidCastException e)
{
e.Data.Add(nameof(columnName), columnName);
throw;
}
return(fieldValue);
}
/// <summary>
/// Formats the values of the current row in the
/// <see cref="ExcelDataReader"/> as a comma delimited string.
/// </summary>
/// <param name="reader">
/// The input <see cref="ExcelDataReader"/>, which acts as the this
/// instance for the extension method.
/// </param>
/// <returns>
/// The values of the current row in the <see cref="ExcelDataReader"/>
/// as a comma delimited string.
/// </returns>
public static string ToDelimitedString(this ExcelDataReader reader)
{
return(reader.ToDelimitedString(includeHeaders: false));
}
/// <summary>
/// Provides strongly-typed access to each of the column values in the <see cref="ExcelDataReader"/>.
/// </summary>
/// <typeparam name="T">The return type of the column.</typeparam>
/// <param name="reader">
/// The input <see cref="ExcelDataReader"/>, which acts as the this
/// instance for the extension method.
/// </param>
/// <param name="columnName">The column name.</param>
/// <param name="nullValue">The value to use as the default.</param>
/// <returns>
/// The value, of type <typeparamref name="T"/>, of the column specified
/// by <paramref name="columnName"/> or <paramref name="nullValue"/> if
/// the field is not found.
/// </returns>
public static T FieldOrDefault <T>(this ExcelDataReader reader, string columnName, T nullValue)
{
return(reader.IsNullOrWhiteSpace(columnName) ? nullValue : reader.Field <T>(columnName));
}
/// <summary>
/// Provides strongly-typed access to each of the column values in the <see cref="ExcelDataReader"/>.
/// </summary>
/// <typeparam name="T">The return type of the column.</typeparam>
/// <param name="reader">
/// The input <see cref="ExcelDataReader"/>, which acts as the this
/// instance for the extension method.
/// </param>
/// <param name="columnIndex">The column index.</param>
/// <param name="nullValue">The value to use as the default.</param>
/// <returns>
/// The value, of type <typeparamref name="T"/>, of the column specified
/// by <paramref name="columnIndex"/> or <paramref name="nullValue"/> if
/// the field is not found.
/// </returns>
public static T FieldOrDefault <T>(this ExcelDataReader reader, int columnIndex, T nullValue)
{
return(reader.IsNullOrWhiteSpace(columnIndex) ? nullValue : reader.Field <T>(columnIndex));
}
/// <summary>
/// Provides strongly-typed access to each of the column values in the <see cref="ExcelDataReader"/>.
/// </summary>
/// <typeparam name="T">The return type of the column.</typeparam>
/// <param name="reader">
/// The input <see cref="ExcelDataReader"/>, which acts as the this
/// instance for the extension method.
/// </param>
/// <param name="columnName">The column name.</param>
/// <returns>
/// The value, of type <typeparamref name="T"/>, of the column specified
/// by <paramref name="columnName"/> or the default for
/// <typeparamref name="T"/> if the field is not found.
/// </returns>
public static T FieldOrDefault <T>(this ExcelDataReader reader, string columnName)
{
return(FieldOrDefault(reader, columnName, default(T) !));
}
/// <summary>
/// Provides strongly-typed access to each of the column values in the <see cref="ExcelDataReader"/>.
/// </summary>
/// <typeparam name="T">The return type of the column.</typeparam>
/// <param name="reader">
/// The input <see cref="ExcelDataReader"/>, which acts as the this
/// instance for the extension method.
/// </param>
/// <param name="columnIndex">The column index.</param>
/// <returns>
/// The value, of type <typeparamref name="T"/>, of the column specified
/// by <paramref name="columnIndex"/> or the default for
/// <typeparamref name="T"/> if the field is not found.
/// </returns>
public static T FieldOrDefault <T>(this ExcelDataReader reader, int columnIndex)
{
return(FieldOrDefault(reader, columnIndex, default(T) !));
}
