/// <summary>
/// Join
/// </summary>
/// <param name="expression">表达式树</param>
/// <param name="sqlWrapper">sql打包对象</param>
/// <returns>SqlWrapper</returns>
public override SqlWrapper Join(BinaryExpression expression, SqlWrapper sqlWrapper)
{
//左侧嵌套
var leftBinary = expression.Left as BinaryExpression;
var isBinaryLeft = leftBinary?.Left is BinaryExpression;
var isBoolMethodCallLeft = (leftBinary?.Left as MethodCallExpression)?.Method.ReturnType == typeof(bool);
var isBinaryRight = leftBinary?.Right is BinaryExpression;
var isBoolMethodCallRight = (leftBinary?.Right as MethodCallExpression)?.Method.ReturnType == typeof(bool);
var leftNested = (isBinaryLeft || isBoolMethodCallLeft) && (isBinaryRight || isBoolMethodCallRight);
if (leftNested)
{
sqlWrapper += "(";
}
SqlExpressionProvider.Join(expression.Left, sqlWrapper);
if (leftNested)
{
sqlWrapper += ")";
}
var operatorIndex = sqlWrapper.Length;
//右侧嵌套
var rightBinary = expression.Right as BinaryExpression;
isBinaryLeft = rightBinary?.Left is BinaryExpression;
isBoolMethodCallLeft = (rightBinary?.Left as MethodCallExpression)?.Method.ReturnType == typeof(bool);
isBinaryRight = rightBinary?.Right is BinaryExpression;
isBoolMethodCallRight = (rightBinary?.Right as MethodCallExpression)?.Method.ReturnType == typeof(bool);
var rightNested = (isBinaryLeft || isBoolMethodCallLeft) && (isBinaryRight || isBoolMethodCallRight);
if (rightNested)
{
sqlWrapper += "(";
}
SqlExpressionProvider.Where(expression.Right, sqlWrapper);
if (rightNested)
{
sqlWrapper += ")";
}
//表达式左侧为bool类型常量且为true时，不进行sql拼接
if (!(expression.Left.NodeType == ExpressionType.Constant && expression.Left.ToObject() is bool b && b))
{
var sqlLength = sqlWrapper.Length;
OperatorResolver(
expression.NodeType,
operatorIndex,
sqlWrapper,
sqlLength - operatorIndex == 5 &&
sqlWrapper.EndsWith("NULL"));
}
return(sqlWrapper);
}
/// <summary>
/// Having
/// </summary>
/// <param name="expression">表达式树</param>
/// <param name="sqlWrapper">sql包装器</param>
/// <returns>SqlWrapper</returns>
public override SqlWrapper Having(ConstantExpression expression, SqlWrapper sqlWrapper)
{
//表达式左侧为bool类型常量
if (expression.NodeType == ExpressionType.Constant && expression.Value is bool res)
{
if (!res && sqlWrapper.EndsWith("AND", "OR"))
{
sqlWrapper += " 1 = 0 ";
}
}
else
{
sqlWrapper.AddDbParameter(expression.Value);
}
return(sqlWrapper);
}
/// <summary>
/// Equals
/// </summary>
/// <param name="expression">表达式树</param>
/// <param name="sqlWrapper">sql打包对象</param>
private static void Equals(MethodCallExpression expression, SqlWrapper sqlWrapper)
{
if (expression.Object != null)
{
SqlExpressionProvider.Where(expression.Object, sqlWrapper);
}
var signIndex = sqlWrapper.Length;
SqlExpressionProvider.Where(expression.Arguments[0], sqlWrapper);
if (sqlWrapper.EndsWith("NULL"))
{
sqlWrapper.Insert(signIndex, " IS ");
}
else
{
sqlWrapper.Insert(signIndex, " = ");
}
}
/// <summary>
/// Where
/// </summary>
/// <param name="expression">表达式树</param>
/// <param name="sqlWrapper">sql包装器</param>
/// <returns>SqlWrapper</returns>
public override SqlWrapper Where(ConditionalExpression expression, SqlWrapper sqlWrapper)
{
var isNot = false;
var testExpression = expression.Test;
//UnaryExpression
if (testExpression is UnaryExpression unaryExpression)
{
isNot = unaryExpression.NodeType == ExpressionType.Not;
testExpression = unaryExpression.Operand;
}
//MethodCallExpression
if (testExpression is MethodCallExpression methodCallExpression)
{
var test = methodCallExpression.ToObject <bool>(out var res);
if (res)
{
if (isNot ? !test : test)
{
SqlExpressionProvider.Where(expression.IfTrue, sqlWrapper);
}
else
{
SqlExpressionProvider.Where(expression.IfFalse, sqlWrapper);
}
}
}
//BinaryExpression
if (testExpression is BinaryExpression binaryExpression)
{
var test = binaryExpression.ToObject <bool>(out var res);
if (!res)
{
test = binaryExpression.Left.ToObject <bool>(out var left);
if (!left)
{
SqlExpressionProvider.Where(binaryExpression.Left, sqlWrapper);
BinaryExpressionResolver.OperatorResolver(
binaryExpression.NodeType,
sqlWrapper.Length,
sqlWrapper,
sqlWrapper.EndsWith("NULL"));
}
var right = false;
if (!left)
{
test = binaryExpression.Right.ToObject <bool>(out right);
}
if (left || !right)
{
SqlExpressionProvider.Where(binaryExpression.Right, sqlWrapper);
BinaryExpressionResolver.OperatorResolver(
binaryExpression.NodeType,
sqlWrapper.Length,
sqlWrapper,
sqlWrapper.EndsWith("NULL"));
}
}
if (isNot ? !test : test)
{
SqlExpressionProvider.Where(expression.IfTrue, sqlWrapper);
}
else
{
SqlExpressionProvider.Where(expression.IfFalse, sqlWrapper);
}
}
return(sqlWrapper);
}
