有一种方法可以重置应用程序设置Settings.Default.Reset()
有没有办法只重置一个属性?就像是
Settings.Default.Properties["MyPropertyName"].Reset();
有一种方法可以重置应用程序设置Settings.Default.Reset()
有没有办法只重置一个属性?就像是
Settings.Default.Properties["MyPropertyName"].Reset();
您可以使用Settings.Default.Properties["MyProperty"].DefaultValue
获取属性的默认值,并将属性值设置为该值。
这是PropertyValue
需要结合Deserialized
(顺序问题)设置的:
public void ResetOneSetting(string propertyName)
{
SettingsPropertyValue propertyToReset = Settings.Default.PropertyValues.OfType<SettingsPropertyValue>().FirstOrDefault(p => p.Name == propertyName);
if (propertyToReset != null)
{
propertyToReset.PropertyValue = propertyToReset.Property.DefaultValue;
propertyToReset.Deserialized = false;
}
}
阅读.NET源代码时找到解决方案:
Settings.Default.PropertyValues["MyPropertyName"].SerializedValue = Settings.Default.Properties["MyPropertyName"].DefaultValue;
Settings.Default.PropertyValues["MyPropertyName"].Deserialized = false;
在我的情况下(.NET Framework 4.6.1,带有System.Drawing.Color
as 设置),我还必须重新分配 中的值Settings.Default
,否则更改似乎被忽略了:
var propertyValue = Settings.Default.PropertyValues["myPropertyName"];
propertyValue.PropertyValue = propertyValue.Property.DefaultValue;
propertyValue.Deserialized = false;
Settings.Default["myPropertyName"] = propertyValue.PropertyValue;
我使用以下代码重置程序中的设置。它利用反射并允许您直接传递属性,而不是手动写出属性名称。它可以像ResetToDefaultValue(TestSettings.Default, x => x.TextFieldStuff);
这样做的好处是它并非所有设置都在其中,Settings
但有些设置可能存储在不同的设置文件中。
//Way to use
//ResetToDefaultValue(TestSettings.Default, x => x.TextFieldStuff);
private static void ResetToDefaultValue<T1, T2>(T1 settings, Expression<Func<T1, T2>> property, bool saveOnReset = true)
{
if (IsSameOrSubclass(typeof(ApplicationSettingsBase), settings.GetType()))
{
ApplicationSettingsBase s = settings as ApplicationSettingsBase;
if (s != null)
{
MemberInfo member = GetMemberInfo(property);
if (!s.PropertyValues[member.Name].UsingDefaultValue)
{
s.PropertyValues[member.Name].PropertyValue = s.PropertyValues[member.Name].Property.DefaultValue;
s.PropertyValues[member.Name].Deserialized = false;
s[member.Name] = s.PropertyValues[member.Name].PropertyValue; //Triggers the property changed
if (saveOnReset)
{
s.Save();
}
}
}
}
}
//Way to use
//GetMemberInfo((TestSettings testSettings) => testSettings.TextFieldStuff);
private static MemberInfo GetMemberInfo<T1, T2>(Expression<Func<T1, T2>> expression)
{
if (IsSameOrSubclass(typeof(MemberExpression), expression.Body.GetType()))
{
MemberExpression member = (MemberExpression)expression.Body;
return member.Member;
}
throw new ArgumentException(@"Expression is not a member access", nameof(expression));
}
private static bool IsSameOrSubclass(Type potentialBase, Type potentialDescendant)
{
return potentialDescendant.IsSubclassOf(potentialBase)
|| potentialDescendant == potentialBase;
}
或者,如果您使用 C# 7.1 或更高版本,则可以使用特征匹配。
//Way to use
//ResetToDefaultValue(TestSettings.Default, x => x.TextFieldStuff);
private static void ResetToDefaultValue<T1, T2>(T1 settings, Expression<Func<T1, T2>> property, bool saveOnReset = true)
{
//Requires C# >= 7.1
if (settings is ApplicationSettingsBase s)
{
MemberInfo member = GetMemberInfo(property);
if (!s.PropertyValues[member.Name].UsingDefaultValue)
{
s.PropertyValues[member.Name].PropertyValue = s.PropertyValues[member.Name].Property.DefaultValue;
s.PropertyValues[member.Name].Deserialized = false;
s[member.Name] = s.PropertyValues[member.Name].PropertyValue;
if (saveOnReset)
{
s.Save();
}
}
}
}
//Way to use
//GetMemberInfo((TestSettings testSettings) => testSettings.TextFieldStuff);
private static MemberInfo GetMemberInfo<T1, T2>(Expression<Func<T1, T2>> expression)
{
//Requires C# >= 7.0
if (expression.Body is MemberExpression member)
{
return member.Member;
}
throw new ArgumentException(@"Expression is not a member access", nameof(expression));
}
当我查看来自@dalleria 和@nikita 的答案时,我遇到了一个问题,即当我尝试获取 DefaultValue (SettingsProperty) 或 PropertyValue (SettingsPropertyValue) 或任何其他相同类型的深层副本时,PropertyValue (SettingsPropertyValue) 意外默认价值。
所以这是我对作为类的一部分的深拷贝函数的简短实现,所以我很抱歉没有将它重构为扩展或工具方法。
private SettingsPropertyValue settingsPropertyValue; // (ex. Settings.Default.PropertyValues["anyPropertyName"])
private SettingsProperty settingsProperty
=> settingsPropertyValue.Property;
/// <summary>
/// Create a deep copy of <paramref name="value"/>.
/// </summary>
/// <param name="value">
/// Should be a deserialized value (ex. <see cref="SettingsPropertyValue.PropertyValue"/>)
/// or a serialized value (ex. <see cref="SettingsProperty.DefaultValue"/>).
/// </param>
/// <param name="isDeserialized">Indicates whether <paramref name="value"/> is deserialized or serialized.</param>
private PropertyType copyValue<PropertyType>(object value, bool isDeserialized)
{
var temporaryPropertyValue = settingsPropertyValue.PropertyValue;
settingsPropertyValue.PropertyValue = value;
if (isDeserialized)
// We have to reassign, otherwise PropertyValue/SerializedValue of SettingsPropertyValue may be defaulted
settingsPropertyValue.SerializedValue = settingsPropertyValue.SerializedValue;
settingsPropertyValue.Deserialized = false;
var propertyValue = (PropertyType)settingsPropertyValue.PropertyValue;
settingsPropertyValue.PropertyValue = temporaryPropertyValue;
return propertyValue;
}
然后,您可以使用以下几行重置 ApplicationSettings/SettingsBase 实例的单个属性:
SettingsBase settings; // (ex. Settings.Default)
public void SetOriginalFromDefault()
{
object defaultValue = settingsProperty.DefaultValue;
defaultValue = copyValue(defaultValue, false);
// We want to set the new value. It also triggers the INotifyPropertyChanged of settings, if the instance is from type ApplicationSettings
settings[settingsProperty.Name] = defaultValue;
}