我需要在我的对象中修剪一些字符串属性,但我不想去所有对象和属性,并且在set属性中做Trim方法(有很多对象,300+和很多字符串属性) .
一个提示:我的所有对象都有一个名为CoreTransaction的超类,所以我可以使用它(带某种反射)来更轻松地完成这个任务.
那可能吗?
谢谢.
Bal*_*a R 37
var stringProperties = obj.GetType().GetProperties()
.Where(p => p.PropertyType == typeof (string));
foreach (var stringProperty in stringProperties)
{
string currentValue = (string) stringProperty.GetValue(obj, null);
stringProperty.SetValue(obj, currentValue.Trim(), null) ;
}
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小智 16
感谢Bala R解决OP的问题.我将您的解决方案转换为扩展方法并修复了空值抛出错误的问题.
/// <summary>Trim all String properties of the given object</summary>
public static TSelf TrimStringProperties<TSelf>(this TSelf input)
{
var stringProperties = input.GetType().GetProperties()
.Where(p => p.PropertyType == typeof(string));
foreach (var stringProperty in stringProperties)
{
string currentValue = (string)stringProperty.GetValue(input, null);
if (currentValue != null)
stringProperty.SetValue(input, currentValue.Trim(), null);
}
return input;
}
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我修复了landi 的答案以容纳子可空对象并处理 IEnumerable 集合(循环遍历对象列表和修剪字符串属性)。我对他的回答进行了编辑,但由于未涉及主题而被拒绝,但那是一堆垃圾。希望这对某人有所帮助,因为landi 的回答不适用于我拥有的所有对象类型。现在确实如此。
public static class ExtensionMethods
{
public static void TrimAllStrings<TSelf>(this TSelf obj)
{
if(obj != null)
{
if(obj is IEnumerable)
{
foreach(var listItem in obj as IEnumerable)
{
listItem.TrimAllStrings();
}
}
else
{
BindingFlags flags = BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.FlattenHierarchy;
foreach (PropertyInfo p in obj.GetType().GetProperties(flags))
{
Type currentNodeType = p.PropertyType;
if (currentNodeType == typeof (String))
{
string currentValue = (string)p.GetValue(obj, null);
if (currentValue != null)
{
p.SetValue(obj, currentValue.Trim(), null);
}
}
// see http://stackoverflow.com/questions/4444908/detecting-native-objects-with-reflection
else if (currentNodeType != typeof (object) && Type.GetTypeCode(currentNodeType) == TypeCode.Object)
{
p.GetValue(obj, null).TrimAllStrings();
}
}
}
}
}
}
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我不确定要更改访问者的行为。这听起来一点也不容易。将修剪添加到您的基类如何?
class CoreTransaction
{
public void Trim()
{
IEnumerable<PropertyInfo> stringProperties =
this.GetType().GetProperties()
.Where(p => p.PropertyType == typeof(string) && p.CanRead && p.CanWrite);
foreach (PropertyInfo property in stringProperties)
{
string value = (string)property.GetValue(this, null);
value = value.Trim();
property.SetValue(this, value, null);
}
}
}
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(另外,请注意检查您的字段是否可以读取和写入。)
编辑: 然后您可以将这样的内容添加到您的基类中,并一次性修剪所有这些内容。WeakReference 类将允许您轻松跟踪您的实例,而不会妨碍垃圾收集器:
class CoreTransaction
{
private static List<WeakReference> allCoreTransactions = new List<WeakReference>();
public CoreTransaction()
{
allCoreTransactions.Add(new WeakReference(this));
}
public static void TrimAll()
{
foreach (WeakReference reference in allCoreTransactions)
{
if (reference.IsAlive)
{
((CoreTransaction)reference.Target).Trim();
}
}
}
}
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我编写了一个扩展方法,它还处理引用类的子类和字符串(如parent.Child.Name)
public static class ExtensionMethods
{
public static void TrimAllStrings<TSelf>(this TSelf obj)
{
BindingFlags flags = BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.FlattenHierarchy;
foreach (PropertyInfo p in obj.GetType().GetProperties(flags))
{
Type currentNodeType = p.PropertyType;
if (currentNodeType == typeof (String))
{
string currentValue = (string)p.GetValue(obj, null);
if (currentValue != null)
{
p.SetValue(obj, currentValue.Trim(), null);
}
}
// see http://stackoverflow.com/questions/4444908/detecting-native-objects-with-reflection
else if (currentNodeType != typeof (object) && Type.GetTypeCode(currentNodeType) == TypeCode.Object)
{
p.GetValue(obj, null).TrimAllStrings();
}
}
}
}
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