72 lines
2.3 KiB
C#
72 lines
2.3 KiB
C#
using System;
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namespace VAR.ExpressionEvaluator
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{
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public class ExpressionEqualsNode : ExpressionBinaryNode
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{
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public ExpressionEqualsNode(IExpressionNode leftNode, IExpressionNode rightNode) :
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base(leftNode, rightNode, EqualsOp)
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{
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}
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private static object EqualsOp(object leftValue, object rightValue)
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{
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if (leftValue is string && rightValue is string)
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{
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return string.Compare((string)leftValue, (string)rightValue) == 0;
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}
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if ((leftValue is string && rightValue == null) || (leftValue == null && rightValue is string))
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{
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return false;
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}
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if (leftValue is string)
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{
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if (string.IsNullOrEmpty((string)leftValue))
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{
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leftValue = null;
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}
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else
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{
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if (decimal.TryParse((string)leftValue, out decimal dec) == false)
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{
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throw new Exception(string.Format("Can't convert to decimal string value \"{0}\"", (string)leftValue));
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}
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leftValue = dec;
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}
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}
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if (rightValue is string)
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{
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if (string.IsNullOrEmpty((string)rightValue))
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{
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leftValue = null;
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}
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else
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{
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if (decimal.TryParse((string)rightValue, out decimal dec) == false)
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{
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throw new Exception(string.Format("Can't convert to decimal string value \"{0}\"", (string)rightValue));
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}
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rightValue = dec;
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}
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}
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if (leftValue == null && rightValue == null)
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{
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return true;
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}
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if (leftValue == null || rightValue == null)
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{
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return false;
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}
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if ((leftValue is decimal) == false || (rightValue is decimal) == false)
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{
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throw new Exception("Can't compare non decimal values");
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}
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return (decimal)leftValue == (decimal)rightValue;
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}
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}
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}
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