MarginsConverter.cs source code in C# .NET

Source code for the .NET framework in C#

                        

Code:

/ FX-1434 / FX-1434 / 1.0 / untmp / whidbey / REDBITS / ndp / fx / src / CommonUI / System / Drawing / Printing / MarginsConverter.cs / 1 / MarginsConverter.cs

                            //------------------------------------------------------------------------------ 
// 
//     Copyright (c) Microsoft Corporation.  All rights reserved.
// 
//----------------------------------------------------------------------------- 

/* 
 */ 
namespace System.Drawing.Printing {
    using System.Runtime.Serialization.Formatters; 
    using System.Runtime.InteropServices;

    using System.Diagnostics;
    using System.Diagnostics.CodeAnalysis; 

    using Microsoft.Win32; 
    using System.Collections; 
    using System.ComponentModel;
    using System.ComponentModel.Design.Serialization; 
    using System.Globalization;
    using System.Reflection;

    ///  
    /// 
    ///    Provides a 
    ///       type converter to convert  to and from various other representations, such as a string. 
    /// 
    public class MarginsConverter : ExpandableObjectConverter { 

        /// 
        /// 
        ///    Determines if a converter can convert an object of the given source 
        ///       type to the native type of the converter.
        ///  
        public override bool CanConvertFrom(ITypeDescriptorContext context, Type sourceType) { 
            if (sourceType == typeof(string)) {
                return true; 
            }
            return base.CanConvertFrom(context, sourceType);
        }
 
        /// 
        ///  
        ///    Gets a value indicating whether this converter can 
        ///       convert an object to the given destination type using the context.
        ///  
        public override bool CanConvertTo(ITypeDescriptorContext context, Type destinationType) {
            if (destinationType == typeof(InstanceDescriptor)) {
                return true;
            } 
            return base.CanConvertTo(context, destinationType);
        } 
 
        /// 
        ///  
        ///      Converts the given object to the converter's native type.
        /// 
        [SuppressMessage("Microsoft.Performance", "CA1808:AvoidCallsThatBoxValueTypes")]
        public override object ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, object value) { 

            string strValue = value as string; 
 
            if (strValue != null) {
 
                string text = strValue.Trim();

                if (text.Length == 0) {
                    return null; 
                }
                else { 
 
                    // Parse 4 integer values.
                    // 
                    if (culture == null) {
                        culture = CultureInfo.CurrentCulture;
                    }
                    char sep = culture.TextInfo.ListSeparator[0]; 
                    string[] tokens = text.Split(new char[] {sep});
                    int[] values = new int[tokens.Length]; 
                    TypeConverter intConverter = TypeDescriptor.GetConverter(typeof(int)); 
                    for (int i = 0; i < values.Length; i++) {
                        // Note: ConvertFromString will raise exception if value cannot be converted. 
                        values[i] = (int)intConverter.ConvertFromString(context, culture, tokens[i]);
                    }

                    if (values.Length != 4) { 
                        throw new ArgumentException(SR.GetString(SR.TextParseFailedFormat,
                                                                  text, 
                                                                  "left, right, top, bottom")); 
                    }
                    return new Margins(values[0], values[1], values[2], values[3]); 
                }
            }

            return base.ConvertFrom(context, culture, value); 
        }
 
        ///  
        /// 
        ///      Converts the given object to another type.  The most common types to convert 
        ///      are to and from a string object.  The default implementation will make a call
        ///      to ToString on the object if the object is valid and if the destination
        ///      type is string.  If this cannot convert to the desitnation type, this will
        ///      throw a NotSupportedException. 
        /// 
        [SuppressMessage("Microsoft.Performance", "CA1800:DoNotCastUnnecessarily")] 
        public override object ConvertTo(ITypeDescriptorContext context, CultureInfo culture, object value, Type destinationType) { 
            if (destinationType == null) {
                throw new ArgumentNullException("destinationType"); 
            }

            if( value is Margins ){
                if (destinationType == typeof(string)) { 
                    Margins margins = (Margins)value;
 
                    if (culture == null) { 
                        culture = CultureInfo.CurrentCulture;
                    } 
                    string sep = culture.TextInfo.ListSeparator + " ";
                    TypeConverter intConverter = TypeDescriptor.GetConverter(typeof(int));
                    string[] args = new string[4];
                    int nArg = 0; 

                    // Note: ConvertToString will raise exception if value cannot be converted. 
                    args[nArg++] = intConverter.ConvertToString(context, culture, margins.Left); 
                    args[nArg++] = intConverter.ConvertToString(context, culture, margins.Right);
                    args[nArg++] = intConverter.ConvertToString(context, culture, margins.Top); 
                    args[nArg++] = intConverter.ConvertToString(context, culture, margins.Bottom);

                    return string.Join(sep, args);
                } 
                if (destinationType == typeof(InstanceDescriptor)) {
                    Margins margins = (Margins)value; 
 
                    ConstructorInfo ctor = typeof(Margins).GetConstructor(new Type[] {
                        typeof(int), typeof(int), typeof(int), typeof(int)}); 

                    if (ctor != null) {
                        return new InstanceDescriptor(ctor, new object[] {
                            margins.Left, margins.Right, margins.Top, margins.Bottom}); 
                    }
                } 
            } 

            return base.ConvertTo(context, culture, value, destinationType); 
        }

        /// 
        ///  
        ///      Creates an instance of this type given a set of property values
        ///      for the object.  This is useful for objects that are immutable, but still 
        ///      want to provide changable properties. 
        /// 
        [SuppressMessage("Microsoft.Performance", "CA1808:AvoidCallsThatBoxValueTypes")] 
        [SuppressMessage("Microsoft.Security", "CA2102:CatchNonClsCompliantExceptionsInGeneralHandlers")]
        public override object CreateInstance(ITypeDescriptorContext context, IDictionary propertyValues) {
            if( propertyValues == null ){
                throw new ArgumentNullException("propertyValues"); 
            }
 
            object left = propertyValues["Left"]; 
            object right = propertyValues["Right"];
            object top = propertyValues["Top"]; 
            object bottom = propertyValues["Bottom"];

            if(left == null || right == null || bottom == null || top == null ||
                !(left is int) || !(right is int) || !(bottom is int) || !(top is int)) { 
                    throw new ArgumentException(SR.GetString(SR.PropertyValueInvalidEntry));
            } 
 
            return new Margins((int)left,
                                (int)right, 
                                (int)top,
                                (int)bottom);
        }
 
        /// 
        ///  
        ///      Determines if changing a value on this object should require a call to 
        ///      CreateInstance to create a new value.
        ///  
        public override bool GetCreateInstanceSupported(ITypeDescriptorContext context) {
            return true;
        }
    } 
}
 
 
// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
// Copyright (c) Microsoft Corporation. All rights reserved.
                        

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