/// <summary>
/// Tries to parse the string and returns a list of <see cref="OrderByExpression"/>.
/// </summary>
/// <param name="source">The source.</param>
/// <param name="expressions">The expressions.</param>
/// <returns>
/// <c>true</c> if the source was parsed into a list of <see cref="OrderByExpression"/>; otherwise,
/// <c>false</c>.
/// </returns>
public static bool TryParseOrderByExpressions(this string source, out OrderByExpression[] expressions)
{
expressions = new OrderByExpression[] { };
if (!string.IsNullOrWhiteSpace(source))
{
var orderByPattern = @"[a-z0-9]+(\s+(asc|desc))?";
var pattern = string.Format(@"^\s*{0}\s*(,\s*{0}\s*)*$", orderByPattern);
if (!Regex.IsMatch(source, pattern, RegexOptions.IgnoreCase))
{
return false;
}
var expressionList = new List<OrderByExpression>();
foreach (var expressionToken in Regex.Replace(source, @"\s+", " ").Split(','))
{
var expressionParts = expressionToken.Trim().Split(' ');
var sortDirection = SortDirection.Ascending;
if (expressionParts.Length == 2 &&
expressionParts[1].Equals("desc", StringComparison.CurrentCultureIgnoreCase))
{
sortDirection = SortDirection.Descending;
}
expressionList.Add(new OrderByExpression(expressionParts[0], sortDirection));
}
expressions = expressionList.ToArray();
}
return true;
}
public void CreateIsProperlyInitialized()
{
var expression = new OrderByExpression("Property", SortDirection.Descending);
Assert.Equal("Property", expression.PropertyName);
Assert.Equal(SortDirection.Descending, expression.Direction);
}
/// <summary>
/// Tries to parse the string and returns a list of <see cref="OrderByExpression"/>.
/// </summary>
/// <param name="source">The source.</param>
/// <param name="expressions">The expressions.</param>
/// <returns>
/// <c>true</c> if the source was parsed into a list of <see cref="OrderByExpression"/>; otherwise,
/// <c>false</c>.
/// </returns>
public static bool TryParseOrderByExpressions(this string source, out OrderByExpression[] expressions)
{
expressions = new OrderByExpression[] { };
if (!string.IsNullOrWhiteSpace(source))
{
var orderByPattern = @"[a-z0-9]+(\s+(asc|desc))?";
var pattern = string.Format(@"^\s*{0}\s*(,\s*{0}\s*)*$", orderByPattern);
if (!Regex.IsMatch(source, pattern, RegexOptions.IgnoreCase))
{
return(false);
}
var expressionList = new List <OrderByExpression>();
foreach (var expressionToken in Regex.Replace(source, @"\s+", " ").Split(','))
{
var expressionParts = expressionToken.Trim().Split(' ');
var sortDirection = SortDirection.Ascending;
if (expressionParts.Length == 2 &&
expressionParts[1].Equals("desc", StringComparison.CurrentCultureIgnoreCase))
{
sortDirection = SortDirection.Descending;
}
expressionList.Add(new OrderByExpression(expressionParts[0], sortDirection));
}
expressions = expressionList.ToArray();
}
return(true);
}
public void TryParseOrderByExpressionsWithValidSourceReturnsExpressions(
string orderBy, OrderByExpression[] expectedExpressions)
{
OrderByExpression[] expressions = null;
var result = orderBy.TryParseOrderByExpressions(out expressions);
Assert.True(result);
var comparer = new DelegateEqualityComparer<OrderByExpression>(
(OrderByExpression x, OrderByExpression y) =>
{
return x.PropertyName == y.PropertyName && x.Direction == y.Direction;
},
(OrderByExpression obj) => { return obj.GetHashCode(); });
Assert.Equal(expectedExpressions, expressions, comparer);
}
