/// <summary>
/// Gets the query condition to determine whether the field value equals <paramref name="value"/>. This field may has multiple values separated by <paramref name="separator"/>.
/// </summary>
/// <param name="field"></param>
/// <param name="value"></param>
/// <param name="separator"></param>
/// <param name="parameterSelector"></param>
/// <returns></returns>
public static ISqlExpression EqualWhenMultiple(ISqlExpression field, string value, string separator, Func <string, ISqlExpression> parameterSelector)
{
if (field == null)
{
throw new ArgumentNullException("field");
}
if (string.IsNullOrWhiteSpace(value))
{
throw new ArgumentException("value is null or empty.", "value");
}
if (string.IsNullOrWhiteSpace(separator))
{
throw new ArgumentException("separator is null or empty.", "separator");
}
return(field.Equal(parameterSelector(value)).Or(field.Like(parameterSelector(GetBeginLikeString(value + separator)))).Or(field.Like(parameterSelector(GetContainLikeString(separator + value + separator)))).Or(field.Like(parameterSelector(GetEndLikeString(separator + value)))));
}