吐槽一下，博客园久了没有上，账号没了，重新申请一个.
cesharp v62版本，内核采用最新的Cef 62，支持最新的Grid布局. 由于官方的cefsharp 采用.net4.5.2开发.怎么办怎么办.我只能用.net4.0.没办法啊，自己拿源码修改兼容呗.
仔细分析源码发现：
1.net4.5.2 引入了 async/await 关键字. 这个其实国外大神已经有源码放出来了，我们把代码直接引入cefsharp 这个工程. 就可以直接在4.0里使用 async/await;
2.net4.5 对task api 做了扩展， 我们只需要在.net4.0实现一下对应的api.就可以了.
3. 源码里面用了很多4.5才有的GetTypeInfo 扩展方法错误. 它返回的类型是typeinfo，不用管它，把GetTypeInfo 删掉. 直接Type 调用就可以了.
4. 对Task静态方法的扩展，需要修改一下，静态方法的调用方式.
以上是要点.下面贴源码：
本段源码是对：async/await的支持：
namespace System.Threading.Tasks{
public static class TaskEx {
public static TaskAwaiter GetAwaiter(this Task task) {
return new TaskAwaiter(task);
}
public static TaskAwaiter<T> GetAwaiter<T>(this Task<T> task) {
return new TaskAwaiter<T>(task);
}
}
public struct TaskAwaiter : INotifyCompletion {
readonly Task task;
internal TaskAwaiter(Task task) {
this.task = task;
}
internal static TaskScheduler TaskScheduler {
get {
if (SynchronizationContext.Current == null) return TaskScheduler.Default;
else return TaskScheduler.FromCurrentSynchronizationContext();
}
}
public bool IsCompleted {
get {
return task.IsCompleted;
}
}
public void OnCompleted(Action continuation) {
this.task.ContinueWith( delegate (Task task) {
continuation();
}
, TaskAwaiter.TaskScheduler);
}
public void GetResult() {
try {
task.Wait();
}
catch (AggregateException ex) {
throw ex.InnerExceptions[0];
}
}
}
public struct TaskAwaiter<T> : INotifyCompletion {
readonly Task<T> task;
internal TaskAwaiter(Task<T> task) {
this.task = task;
}
public bool IsCompleted {
get {
return task.IsCompleted;
}
}
public void OnCompleted(Action continuation) {
this.task.ContinueWith( delegate (Task<T> task) {
continuation();
}
, TaskAwaiter.TaskScheduler);
}
public T GetResult() {
try {
return task.Result;
}
catch (AggregateException ex) {
throw ex.InnerExceptions[0];
}
}
}
}
namespace System.Runtime.CompilerServices{
public interface INotifyCompletion {
void OnCompleted(Action continuation);
}
public interface ICriticalNotifyCompletion : INotifyCompletion {
[SecurityCritical] void UnsafeOnCompleted(Action continuation);
}
public interface IAsyncStateMachine {
void MoveNext();
void SetStateMachine(IAsyncStateMachine stateMachine);
}
public struct AsyncVoidMethodBuilder {
public static AsyncVoidMethodBuilder Create() {
return new AsyncVoidMethodBuilder();
}
public void SetException(Exception exception) {
throw exception;
}
public void SetResult() {
}
public void SetStateMachine(IAsyncStateMachine stateMachine) {
// Should not get called as we don't implement the optimization that this method is used for. throw new NotImplementedException();
}
public void Start<TStateMachine>(ref TStateMachine stateMachine) where TStateMachine : IAsyncStateMachine {
stateMachine.MoveNext();
}
public void AwaitOnCompleted<TAwaiter, TStateMachine>(ref TAwaiter awaiter, ref TStateMachine stateMachine) where TAwaiter : INotifyCompletion where TStateMachine : IAsyncStateMachine {
awaiter.OnCompleted(stateMachine.MoveNext);
}
public void AwaitUnsafeOnCompleted<TAwaiter, TStateMachine>(ref TAwaiter awaiter, ref TStateMachine stateMachine) where TAwaiter : ICriticalNotifyCompletion where TStateMachine : IAsyncStateMachine {
awaiter.OnCompleted(stateMachine.MoveNext);
}
}
public struct AsyncTaskMethodBuilder {
TaskCompletionSource<object> tcs;
public Task Task {
get {
return tcs.Task;
}
}
public static AsyncTaskMethodBuilder Create() {
AsyncTaskMethodBuilder b;
b.tcs = new TaskCompletionSource<object>();
return b;
}
public void Start<TStateMachine>(ref TStateMachine stateMachine) where TStateMachine : IAsyncStateMachine {
stateMachine.MoveNext();
}
public void SetStateMachine(IAsyncStateMachine stateMachine) {
// Should not get called as we don't implement the optimization that this method is used for. throw new NotImplementedException();
}
public void AwaitOnCompleted<TAwaiter, TStateMachine>(ref TAwaiter awaiter, ref TStateMachine stateMachine) where TAwaiter : INotifyCompletion where TStateMachine : IAsyncStateMachine {
awaiter.OnCompleted(stateMachine.MoveNext);
}
public void AwaitUnsafeOnCompleted<TAwaiter, TStateMachine>(ref TAwaiter awaiter, ref TStateMachine stateMachine) where TAwaiter : ICriticalNotifyCompletion where TStateMachine : IAsyncStateMachine {
awaiter.OnCompleted(stateMachine.MoveNext);
}
public void SetResult() {
tcs.SetResult(null);
}
public void SetException(Exception exception) {
tcs.SetException(exception);
}
}
public struct AsyncTaskMethodBuilder<T> {
TaskCompletionSource<T> tcs;
public Task<T> Task {
get {
return tcs.Task;
}
}
public static AsyncTaskMethodBuilder<T> Create() {
AsyncTaskMethodBuilder<T> b;
b.tcs = new TaskCompletionSource<T>();
return b;
}
public void Start<TStateMachine>(ref TStateMachine stateMachine) where TStateMachine : IAsyncStateMachine {
stateMachine.MoveNext();
}
public void SetStateMachine(IAsyncStateMachine stateMachine) {
// Should not get called as we don't implement the optimization that this method is used for. throw new NotImplementedException();
}
public void AwaitOnCompleted<TAwaiter, TStateMachine>(ref TAwaiter awaiter, ref TStateMachine stateMachine) where TAwaiter : INotifyCompletion where TStateMachine : IAsyncStateMachine {
awaiter.OnCompleted(stateMachine.MoveNext);
}
public void AwaitUnsafeOnCompleted<TAwaiter, TStateMachine>(ref TAwaiter awaiter, ref TStateMachine stateMachine) where TAwaiter : ICriticalNotifyCompletion where TStateMachine : IAsyncStateMachine {
AwaitOnCompleted(ref awaiter, ref stateMachine);
}
public void SetResult(T result) {
tcs.SetResult(result);
}
public void SetException(Exception exception) {
tcs.SetException(exception);
}
}
}
这段是对 Task 的扩展
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
namespace CefSharp{
public class TaskEx {
public static Task<T> FromResult<T>(T t) {
return Task.Factory.StartNew<T>(() => t);
}
public static Task Run(Action action) {
var tcs = new TaskCompletionSource<object>();
new Thread(() => {
try {
action();
tcs.SetResult(null);
}
catch (Exception ex) {
tcs.SetException(ex);
}
}
) {
IsBackground = true }
.Start();
return tcs.Task;
}
public static Task<TResult> Run<TResult>(Func<TResult> function) {
var tcs = new TaskCompletionSource<TResult>();
new Thread(() => {
try {
tcs.SetResult(function());
}
catch (Exception ex) {
tcs.SetException(ex);
}
}
) {
IsBackground = true }
.Start();
return tcs.Task;
}
public static Task Delay(int milliseconds) {
var tcs = new TaskCompletionSource<object>();
var timer = new System.Timers.Timer(milliseconds) {
AutoReset = false }
;
timer.Elapsed += delegate {
timer.Dispose();
tcs.SetResult(null);
}
;
timer.Start();
return tcs.Task;
}
}
}
把在C#内添加以上代码里， 遇到 Task.Run 的时候，替换成 TaskEx.Run，遇到 Task.Delay 替换为TaskEx.Delay.
还有报 GetTypeInfo 这个错误的地方，删之就Ok了。
以上这篇CefSharp v62修改方法(支持.net4.0)就是小编分享给大家的全部内容了，希望能给大家一个参考，也希望大家多多支持脚本之家。
