PropertyExpression.cs source code in C# .NET

Source code for the .NET framework in C#

                        
Code:

                         / 4.0 / 4.0 / DEVDIV_TFS / Dev10 / Releases / RTMRel / ndp / fx / src / xsp / System / Extensions / UI / WebControls / Expressions / PropertyExpression.cs / 1305376 / PropertyExpression.cs
                        

                        
                            #if ORYX_VNEXT 
namespace Microsoft.Web.Data.UI.WebControls.Expressions {
    using System.Web;
    using System.Web.UI.WebControls;
#else 
namespace System.Web.UI.WebControls.Expressions {
#endif 
    using System; 
    using System.Collections.Generic;
    using System.Security.Permissions; 
    using System.Web.UI;
    using System.Linq.Expressions;
    using System.Linq;
 
    public class PropertyExpression : ParameterDataSourceExpression {
        public override IQueryable GetQueryable(IQueryable source) { 
            if (source == null) { 
                return null;
            } 

            IDictionary values = GetValues();
            List equalsExpressions = new List();
            ParameterExpression parameterExpression = Expression.Parameter(source.ElementType, String.Empty); 

            foreach (KeyValuePair pair in values) { 
                if (!String.IsNullOrEmpty(pair.Key)) { 
                    // Create the property expression
                    Expression property = ExpressionHelper.CreatePropertyExpression(parameterExpression, pair.Key); 
                    // Get the value
                    object value = ExpressionHelper.BuildObjectValue(pair.Value, property.Type);
                    // Create Property == Value and '&&' the expressions together
                    if (value != null) { 
                        Expression valueExpression = Expression.Constant(value, property.Type);
                        Expression equalsExpression = Expression.Equal(property, valueExpression); 
                        equalsExpressions.Add(equalsExpression); 
                    }
                } 
            }

            if (equalsExpressions.Any()) {
                Expression body = ExpressionHelper.And(equalsExpressions); 
                return ExpressionHelper.Where(source, Expression.Lambda(body, parameterExpression));
            } 
 
            return source;
        } 
    }
}

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
// Copyright (c) Microsoft Corporation. All rights reserved.
#if ORYX_VNEXT 
namespace Microsoft.Web.Data.UI.WebControls.Expressions {
    using System.Web;
    using System.Web.UI.WebControls;
#else 
namespace System.Web.UI.WebControls.Expressions {
#endif 
    using System; 
    using System.Collections.Generic;
    using System.Security.Permissions; 
    using System.Web.UI;
    using System.Linq.Expressions;
    using System.Linq;
 
    public class PropertyExpression : ParameterDataSourceExpression {
        public override IQueryable GetQueryable(IQueryable source) { 
            if (source == null) { 
                return null;
            } 

            IDictionary values = GetValues();
            List equalsExpressions = new List();
            ParameterExpression parameterExpression = Expression.Parameter(source.ElementType, String.Empty); 

            foreach (KeyValuePair pair in values) { 
                if (!String.IsNullOrEmpty(pair.Key)) { 
                    // Create the property expression
                    Expression property = ExpressionHelper.CreatePropertyExpression(parameterExpression, pair.Key); 
                    // Get the value
                    object value = ExpressionHelper.BuildObjectValue(pair.Value, property.Type);
                    // Create Property == Value and '&&' the expressions together
                    if (value != null) { 
                        Expression valueExpression = Expression.Constant(value, property.Type);
                        Expression equalsExpression = Expression.Equal(property, valueExpression); 
                        equalsExpressions.Add(equalsExpression); 
                    }
                } 
            }

            if (equalsExpressions.Any()) {
                Expression body = ExpressionHelper.And(equalsExpressions); 
                return ExpressionHelper.Where(source, Expression.Lambda(body, parameterExpression));
            } 
 
            return source;
        } 
    }
}

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
// Copyright (c) Microsoft Corporation. All rights reserved.

Link Menu

Network programming in C#, Network Programming in VB.NET, Network Programming in .NET
This book is available now!
Buy at Amazon US or
Buy at Amazon UK