//------------------------------------------------------
//
// Internal Methods
//
//------------------------------------------------------
#region Internal Methods
internal void SetMarshalData <T>(T uiaCondition)
where T : struct
{
// Takes one of the interop UiaCondition classes (from UiaCoreApi.cs), and allocs
// a SafeHandle with associated unmanaged memory - can then pass that to the UIA APIs.
_safeHandle = SafeConditionMemoryHandle.AllocateConditionHandle(uiaCondition);
}
// used by And/Or conditions to allocate an array of pointers to other conditions
internal static SafeConditionMemoryHandle AllocateConditionArrayHandle(Condition [] conditions)
{
// Allocate SafeHandle first to avoid failure later.
SafeConditionMemoryHandle sh = new SafeConditionMemoryHandle();
int intPtrSize = Marshal.SizeOf(typeof(IntPtr));
try { }
finally
{
IntPtr mem = Marshal.AllocCoTaskMem(conditions.Length * intPtrSize);
sh.SetHandle(mem);
}
unsafe
// Suppress "Exposing unsafe code thru public interface" UiaCoreApi is trusted
#pragma warning suppress 56505
{
IntPtr *pdata = (IntPtr *)sh.handle;
for (int i = 0; i < conditions.Length; i++)
{
*pdata++ = conditions[i]._safeHandle.handle;
}
}
return(sh);
}
// used by And/Or conditions to allocate an array of pointers to other conditions
internal static SafeConditionMemoryHandle AllocateConditionArrayHandle(Condition [] conditions)
{
// Allocate SafeHandle first to avoid failure later.
SafeConditionMemoryHandle sh = new SafeConditionMemoryHandle();
int intPtrSize = Marshal.SizeOf(typeof(IntPtr));
#pragma warning disable SYSLIB0004 // The Constrained Execution Region (CER) feature is not supported.
RuntimeHelpers.PrepareConstrainedRegions(); // ensures that the following finally block is atomic
#pragma warning restore SYSLIB0004 // The Constrained Execution Region (CER) feature is not supported.
try { }
finally
{
IntPtr mem = Marshal.AllocCoTaskMem(conditions.Length * intPtrSize);
sh.SetHandle(mem);
}
unsafe
// Suppress "Exposing unsafe code thru public interface" UiaCoreApi is trusted
#pragma warning suppress 56505
{
IntPtr *pdata = (IntPtr *)sh.handle;
for (int i = 0; i < conditions.Length; i++)
{
*pdata++ = conditions[i]._safeHandle.handle;
}
}
return(sh);
}
// uiaCondition is one of the Uia condition structs - eg UiaCoreApi.UiaAndOrCondition
internal static SafeConditionMemoryHandle AllocateConditionHandle(object uiaCondition)
{
// Allocate SafeHandle first to avoid failure later.
SafeConditionMemoryHandle sh = new SafeConditionMemoryHandle();
int size = Marshal.SizeOf(uiaCondition);
try { }
finally
{
IntPtr mem = Marshal.AllocCoTaskMem(size);
sh.SetHandle(mem);
}
Marshal.StructureToPtr(uiaCondition, sh.handle, false);
return(sh);
}
// uiaCondition is one of the Uia condition structs - eg UiaCoreApi.UiaAndOrCondition
internal static SafeConditionMemoryHandle AllocateConditionHandle(object uiaCondition)
{
// Allocate SafeHandle first to avoid failure later.
SafeConditionMemoryHandle sh = new SafeConditionMemoryHandle();
int size = Marshal.SizeOf(uiaCondition);
RuntimeHelpers.PrepareConstrainedRegions(); // ensures that the following finally block is atomic
try { }
finally
{
IntPtr mem = Marshal.AllocCoTaskMem(size);
sh.SetHandle(mem);
}
Marshal.StructureToPtr(uiaCondition, sh.handle, false);
return(sh);
}
//------------------------------------------------------
//
// Constructors
//
//------------------------------------------------------
#region Constructors
/// <summary>
/// Constructor to create a condition that is true if all of the sub-conditions are true
/// </summary>
/// <param name="conditions">One or more sub-condition</param>
public AndCondition(params Condition [] conditions)
{
Misc.ValidateArgumentNonNull(conditions, "conditions");
Misc.ValidateArgument(conditions.Length >= 2, SRID.MustBeAtLeastTwoConditions);
foreach (Condition condition in conditions)
{
Misc.ValidateArgumentNonNull(condition, "conditions");
}
// clone array to prevent accidental tampering
_conditions = (Condition [] )conditions.Clone();
_conditionArrayHandle = SafeConditionMemoryHandle.AllocateConditionArrayHandle(_conditions);
// DangerousGetHandle() reminds us that the IntPtr we get back could be collected/released/recycled. We're safe here,
// because the Conditions are structured in a tree, with the root one (which gets passed to the Uia API) keeping all
// others - and their associated data - alive. (Recycling isn't an issue as these are immutable classes.)
SetMarshalData(new UiaCoreApi.UiaAndOrCondition(UiaCoreApi.ConditionType.And, _conditionArrayHandle.DangerousGetHandle(), _conditions.Length));
}
// uiaCondition is one of the Uia condition structs - eg UiaCoreApi.UiaAndOrCondition
internal static SafeConditionMemoryHandle AllocateConditionHandle(object uiaCondition)
{
// Allocate SafeHandle first to avoid failure later.
SafeConditionMemoryHandle sh = new SafeConditionMemoryHandle();
int size = Marshal.SizeOf(uiaCondition);
#pragma warning disable SYSLIB0004 // The Constrained Execution Region (CER) feature is not supported.
RuntimeHelpers.PrepareConstrainedRegions(); // ensures that the following finally block is atomic
#pragma warning restore SYSLIB0004 // The Constrained Execution Region (CER) feature is not supported.
try { }
finally
{
IntPtr mem = Marshal.AllocCoTaskMem(size);
sh.SetHandle(mem);
}
Marshal.StructureToPtr(uiaCondition, sh.handle, false);
return(sh);
}
