/// <summary>
/// create conversion code
/// </summary>
/// <param name="sourceType"></param>
/// <param name="sourceCode"></param>
/// <param name="targetType"></param>
/// <returns>conversion code converting sourceCode to the targetType</returns>
public static CodeExpression GetConversionCode(RaisDataType sourceType, CodeExpression sourceCode, RaisDataType targetType, CodeStatementCollection supprtStatements)
{
CodeExpression codeRet;
if (sourceType.IsSameType(targetType))
{
return(sourceCode);
}
if (targetType.IsLibType || sourceType.IsLibType)
{
if (MathNode.GetTypeConversion != null)
{
return(MathNode.GetTypeConversion(targetType.Type, sourceCode, sourceType.Type, supprtStatements));
}
return(CastOrConvert(sourceCode, sourceType.Type, targetType.Type, supprtStatements));
}
string srcType = sourceType.DevType.TypeString;
string tgtType = targetType.DevType.TypeString;
if (srcType.StartsWith(tgtType))
{
return(sourceCode);
}
if (tgtType.StartsWith(srcType))
{
return(new CodeCastExpression(tgtType, VPLUtil.GetCoreExpressionFromCast(sourceCode)));
}
TypeConverter converter = TypeDescriptor.GetConverter(targetType.Type);
if (converter.CanConvertFrom(sourceType.Type))
{
MathNode.AddImportLocation(typeof(TypeConverter).Assembly.Location);
string converterName = "conv" + targetType.Type.Name;
if (!MathNodeVariable.VariableDeclared(supprtStatements, converterName))
{
CodeVariableDeclarationStatement cs1 = new CodeVariableDeclarationStatement(
typeof(TypeConverter), converterName,
new CodeMethodInvokeExpression(
new CodeTypeReferenceExpression(typeof(TypeDescriptor)), "GetConverter",
new CodeExpression[] { new CodeSnippetExpression("typeof(" + tgtType + ")") }));
supprtStatements.Add(cs1);
}
//=================================================
//
codeRet = new CodeCastExpression(tgtType,
new CodeMethodInvokeExpression(
new CodeVariableReferenceExpression(converterName), "ConvertFrom",
new CodeExpression[] { sourceCode }));
MathNode.Trace("\tcode 102: source type:{0}, target type:{1} result=converter.ConvertFrom(code);", sourceType, targetType);
}
else
{
codeRet = CastOrConvert(sourceCode, sourceType.Type, targetType.Type, supprtStatements);
}
return(codeRet);
}