关于

可以通过 Snoop 查看 WPF 程序的 Visual Tree，更多介绍请看 snoopwpf

快速开始

一、下载 snoopwpf.msi

安装后打开，选择自己的程序，点击 snoop（望远镜）

二、筛选

点击左侧下拉列表，选择 Show only elements with binding errors

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三、点击出错的节点，右侧点击 Properties，然后滚动表格，找到标红的一行

四、右键选择 Display Binding Errors

五、分析错误

System.Windows.Data Error: 23 : Cannot convert '<null>' from type '<null>' to type 'System.Double' for 'en-US' culture with default conversions; consider using Converter property of Binding. NotSupportedException:'System.NotSupportedException: DoubleConverter 无法从 (null) 转换。在 System.ComponentModel.TypeConverter.GetConvertFromException(Object value)在 System.ComponentModel.TypeConverter.ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, Object value)在 System.ComponentModel.BaseNumberConverter.ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, Object value)在 MS.Internal.Data.DefaultValueConverter.ConvertHelper(Object o, Type destinationType, DependencyObject targetElement, CultureInfo culture, Boolean isForward)'
System.Windows.Data Error: 6 : 'ObjectSourceConverter' converter failed to convert value '<null>' (type '<null>'); fallback value will be used, if available. BindingExpression:Path=Tag; DataItem='ProgressBar' (Name=''); target element is 'Rectangle' (Name=''); target property is 'RadiusX' (type 'Double') NotSupportedException:'System.NotSupportedException: DoubleConverter 无法从 (null) 转换。在 MS.Internal.Data.DefaultValueConverter.ConvertHelper(Object o, Type destinationType, DependencyObject targetElement, CultureInfo culture, Boolean isForward)在 MS.Internal.Data.ObjectSourceConverter.Convert(Object o, Type type, Object parameter, CultureInfo culture)在 System.Windows.Data.BindingExpression.ConvertHelper(IValueConverter converter, Object value, Type targetType, Object parameter, CultureInfo culture)'