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//------------------------------------------------------------------------------
// <copyright file="PointConverter.cs" company="Microsoft">
// Copyright (c) Microsoft Corporation. All rights reserved.
// </copyright>
//------------------------------------------------------------------------------
/*
*/
namespace System.Drawing {
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;
/// <include file='doc\PointConverter.uex' path='docs/doc[@for="PointConverter"]/*' />
/// <devdoc>
/// PointConverter is a class that can be used to convert
/// Point from one data type to another. Access this
/// class through the TypeDescriptor.
/// </devdoc>
public class PointConverter : TypeConverter {
/// <include file='doc\PointConverter.uex' path='docs/doc[@for="PointConverter.CanConvertFrom"]/*' />
/// <devdoc>
/// Determines if this converter can convert an object in the given source
/// type to the native type of the converter.
/// </devdoc>
public override bool CanConvertFrom(ITypeDescriptorContext context, Type sourceType) {
if (sourceType == typeof(string)) {
return true;
}
return base.CanConvertFrom(context, sourceType);
}
/// <include file='doc\PointConverter.uex' path='docs/doc[@for="PointConverter.CanConvertTo"]/*' />
/// <devdoc>
/// <para>Gets a value indicating whether this converter can
/// convert an object to the given destination type using the context.</para>
/// </devdoc>
public override bool CanConvertTo(ITypeDescriptorContext context, Type destinationType) {
if (destinationType == typeof(InstanceDescriptor)) {
return true;
}
return base.CanConvertTo(context, destinationType);
}
/// <include file='doc\PointConverter.uex' path='docs/doc[@for="PointConverter.ConvertFrom"]/*' />
/// <devdoc>
/// Converts the given object to the converter's native type.
/// </devdoc>
[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 2 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 == 2) {
return new Point(values[0], values[1]);
}
else {
throw new ArgumentException(SR.GetString(SR.TextParseFailedFormat,
text,
"x, y"));
}
}
}
return base.ConvertFrom(context, culture, value);
}
/// <include file='doc\PointConverter.uex' path='docs/doc[@for="PointConverter.ConvertTo"]/*' />
/// <devdoc>
/// 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.
/// </devdoc>
public override object ConvertTo(ITypeDescriptorContext context, CultureInfo culture, object value, Type destinationType) {
if (destinationType == null) {
throw new ArgumentNullException("destinationType");
}
if(value is Point){
if (destinationType == typeof(string)) {
Point pt = (Point)value;
if (culture == null) {
culture = CultureInfo.CurrentCulture;
}
string sep = culture.TextInfo.ListSeparator + " ";
TypeConverter intConverter = TypeDescriptor.GetConverter(typeof(int));
string[] args = new string[2];
int nArg = 0;
// Note: ConvertToString will raise exception if value cannot be converted.
args[nArg++] = intConverter.ConvertToString(context, culture, pt.X);
args[nArg++] = intConverter.ConvertToString(context, culture, pt.Y);
return string.Join(sep, args);
}
if (destinationType == typeof(InstanceDescriptor)) {
Point pt = (Point)value;
ConstructorInfo ctor = typeof(Point).GetConstructor(new Type[] {typeof(int), typeof(int)});
if (ctor != null) {
return new InstanceDescriptor(ctor, new object[] {pt.X, pt.Y});
}
}
}
return base.ConvertTo(context, culture, value, destinationType);
}
/// <include file='doc\PointConverter.uex' path='docs/doc[@for="PointConverter.CreateInstance"]/*' />
/// <devdoc>
/// 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.
/// </devdoc>
[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 x = propertyValues["X"];
object y = propertyValues["Y"];
if(x == null || y == null ||
!(x is int) || !(y is int)) {
throw new ArgumentException(SR.GetString(SR.PropertyValueInvalidEntry));
}
return new Point((int)x,
(int)y);
}
/// <include file='doc\PointConverter.uex' path='docs/doc[@for="PointConverter.GetCreateInstanceSupported"]/*' />
/// <devdoc>
/// Determines if changing a value on this object should require a call to
/// CreateInstance to create a new value.
/// </devdoc>
public override bool GetCreateInstanceSupported(ITypeDescriptorContext context) {
return true;
}
/// <include file='doc\PointConverter.uex' path='docs/doc[@for="PointConverter.GetProperties"]/*' />
/// <devdoc>
/// Retrieves the set of properties for this type. By default, a type has
/// does not return any properties. An easy implementation of this method
/// can just call TypeDescriptor.GetProperties for the correct data type.
/// </devdoc>
public override PropertyDescriptorCollection GetProperties(ITypeDescriptorContext context, object value, Attribute[] attributes) {
PropertyDescriptorCollection props = TypeDescriptor.GetProperties(typeof(Point), attributes);
return props.Sort(new string[] {"X", "Y"});
}
/// <include file='doc\PointConverter.uex' path='docs/doc[@for="PointConverter.GetPropertiesSupported"]/*' />
/// <devdoc>
/// Determines if this object supports properties. By default, this
/// is false.
/// </devdoc>
public override bool GetPropertiesSupported(ITypeDescriptorContext context) {
return true;
}
}
}
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