/// <summary>
/// 编译模板
/// </summary>
/// <param name="template"></param>
/// <param name="output"></param>
/// <returns></returns>
public Expression <Action <DynamicModel> > Build(string template, OutPutProvide output)
{
var buffer = Encoding.UTF8.GetBytes(template);
using var memory = new MemoryStream(buffer);
using var reader = new StreamReader(memory);
var scope = new ScopeBlockContext();
CreateNodeContextRange(reader, scope, output);
scope.ConvertToExpression();
return(Expression.Lambda <Action <DynamicModel> >(scope.NdExpression, scope.Root));
}
/// <summary>
/// 指定输出类创建表达式提供类
/// </summary>
/// <param name="outPut"></param>
public PrintExpressionProvide(OutPutProvide outPut)
{
_outPut = outPut;
}
/// <summary>
/// 将语法解析为节点树
/// </summary>
/// <param name="reader"></param>
/// <param name="ParentNode"></param>
/// <param name="output"></param>
private void CreateNodeContextRange(StreamReader reader, NodeBlockContext ParentNode, OutPutProvide output)
{
while (true)
{
string line = reader.ReadLine();
if (line == null)
{
return;
}
_lineNumber++;
NodeType type = GetNodeType(line);
NodeContext last = ParentNode.Nodes.LastOrDefault();
if (last?.NdType == NodeType.IF || last?.NdType == NodeType.ELSEIF)
{
if (type != NodeType.ELSEIF && type != NodeType.ELSE)
{
for (int i = ParentNode.Nodes.Count - 1; i >= 0; i--)
{
NodeContext item = ParentNode.Nodes[i];
if (item.NdType != NodeType.ELSEIF && item.NdType != NodeType.IF)
{
break;
}
item.ConvertToExpression();
}
}
}
switch (type)
{
case NodeType.IF:
NodeBlockContext block = new IFNodeContext(line, ParentNode, output);
CreateNodeContextRange(reader, block, output);
ParentNode.Nodes.Add(block);
break;
case NodeType.ELSEIF:
block = new ELSEIFNodeContext(line, ParentNode, output);
CreateNodeContextRange(reader, block, output);
if (last is IFNodeContext ifnd1)
{
ifnd1.ELSENode = block;
}
else if (last is ELSEIFNodeContext elnd1)
{
elnd1.ELSENode = block;
}
else
{
throw new Exception($"第{_lineNumber}行语法错误,elseif必须在 if 或 elseif 之后");
}
ParentNode.Nodes.Add(block);
break;
case NodeType.ELSE:
block = new ELSENodeContext(line, ParentNode, output);
CreateNodeContextRange(reader, block, output);
block.ConvertToExpression();
if (last is IFNodeContext ifnd)
{
ifnd.ELSENode = block;
}
else if (last is ELSEIFNodeContext elnd)
{
elnd.ELSENode = block;
}
else
{
throw new Exception($"第{_lineNumber}行语法错误,else 必须在 if 或 elseif之后");
}
for (int i = ParentNode.Nodes.Count - 1; i >= 0; i--)
{
NodeContext item = ParentNode.Nodes[i];
if (item.NdType != NodeType.ELSEIF && item.NdType != NodeType.IF)
{
break;
}
item.ConvertToExpression();
}
ParentNode.Nodes.Add(block);
break;
case NodeType.EACH:
block = new EACHNodeContext(line, ParentNode, output);
CreateNodeContextRange(reader, block, output);
block.ConvertToExpression();
ParentNode.Nodes.Add(block);
break;
case NodeType.PRINT:
NodeContext node = new PRINTNodeContext(line, ParentNode, output);
node.ConvertToExpression();
ParentNode.Nodes.Add(node);
break;
case NodeType.STRING:
node = new STRINGNodeContext(line, ParentNode, output);
node.ConvertToExpression();
ParentNode.Nodes.Add(node);
break;
case NodeType.SET:
node = new SETNodeContext(line, ParentNode, output);
node.ConvertToExpression();
ParentNode.Nodes.Add(node);
break;
case NodeType.OPER:
node = new OperNodeContext(line, ParentNode, output);
node.ConvertToExpression();
ParentNode.Nodes.Add(node);
break;
case NodeType.ENDIF:
case NodeType.ENDELSEIF:
case NodeType.ENDELSE:
case NodeType.ENDEACH:
return;
default:
throw new Exception($"{type}是不受支持的节点类型");
}
}
}
