I am trying to verify whether a variable that is passed can be converted to a specific type. I have tried the following but can't get it to compile so I assume I'm going about it the wrong way (I'm new to C#)
string myType = "System.Int32";
string myValue = "42";
bool canBeCast = false;
try
{
// try to convert the value to it's intended type to see if it's valid.
var result = (Type.GetType(typeString))dataValue;
canBeCast = true;
}
catch
{
canBeCast = false;
}
I'm basically trying to avoid a massive switch statement along the lines of
switch(myType){
case "System.Int32":
try
{
var convertedValue = Convert.ToInt32(myValue);
}
catch (Exception)
{
canBeConverted = false;
}
break;
case "another type":
...
}
EDIT:
Ok, basically I have a db table of known input types that looks like:
CREATE TABLE [dbo].[MetadataTypes] (
[typeName] VARCHAR (50) NOT NULL,
[dataType] VARCHAR (50) NOT NULL,
[typeRegex] VARCHAR (255) NULL
);
which may have data such as
"StartTime","System.DateTime",null
"TicketId","System.String","$[Ff][0-9]{7}^"
And the input to my function would be a KeyValuePair along the lines of
myInput = new KeyValuePair<string,string>("StartTime","31/12/2010 12:00");
I need to check that the value of the KeyValuePair is of the correct datatype expected by the MetaDataType.
EDIT FOR ANSWER:
Leon got really close to the solution I finally came up with.
For reference my function now looks like this:
public Boolean ValidateMetadata(KeyValuePair<string, string> dataItem)
{
// Look for known metadata with name match
MetadataType type = _repository.GetMetadataTypes().SingleOrDefault(t => t.typeName == dataItem.Key);
if (type == null) { return false; }
// Get the data type and try to match to the passed in data item.
Boolean isCorrectType = false;
string typeString = type.dataType;
string dataValue = dataItem.Value;
try
{
var cValue = Convert.ChangeType(dataValue, Type.GetType(typeString));
isCorrectType = true;
}
catch
{
isCorrectType = false;
}
//TODO: Validate against possible regex here....
return isCorrectType;
}
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