/// <summary>
/// Returns the name of the function as it is defined in the target DBMS.
/// </summary>
/// <param name="stringFunctionExpressionType">The <see cref="DbStringFunctionExpressionType"/> that specifies the function name to return.</param>
/// <returns><see cref="string"/></returns>
protected virtual string GetStringFunctionBody(DbStringFunctionExpressionType stringFunctionExpressionType)
{
switch (stringFunctionExpressionType)
{
case DbStringFunctionExpressionType.Length:
return("LEN({0})");
case DbStringFunctionExpressionType.Replace:
return("REPLACE({0})");
case DbStringFunctionExpressionType.Reverse:
return("REVERSE({0})");
case DbStringFunctionExpressionType.ToLower:
return("LOWER({0})");
case DbStringFunctionExpressionType.ToUpper:
return("UPPER({0})");
case DbStringFunctionExpressionType.Trim:
return("LTRIM(RTRIM({0}))");
case DbStringFunctionExpressionType.TrimStart:
return("LTRIM({0})");
case DbStringFunctionExpressionType.TrimEnd:
return("RTRIM({0})");
case DbStringFunctionExpressionType.SoundEx:
return("SOUNDEX({0})");
case DbStringFunctionExpressionType.SubString:
return("SUBSTR({0})");
default:
throw new ArgumentOutOfRangeException("stringFunctionExpressionType", stringFunctionExpressionType, " is not supported");
}
}
/// <summary>
/// Initializes a new instance of the <see cref="DbStringFunctionExpression"/> class.
/// </summary>
/// <param name="stringFunctionExpressionType">The <see cref="DbStringFunctionExpressionType"/> of the <see cref="DbStringFunctionExpression"/>.</param>
/// <param name="arguments">The arguments used when calling the function.</param>
internal DbStringFunctionExpression(DbStringFunctionExpressionType stringFunctionExpressionType, DbExpression[] arguments) : base(DbFunctionExpressionType.String, arguments)
{
StringFunctionExpressionType = stringFunctionExpressionType;
}
private void ValidateStringFunctionExpression(DbStringFunctionExpression stringFunctionExpression, DbStringFunctionExpressionType stringFunctionExpressionType)
{
Assert.IsTrue(stringFunctionExpression.ExpressionType == DbExpressionType.Function);
Assert.IsTrue(stringFunctionExpression.StringFunctionExpressionType == stringFunctionExpressionType);
Assert.IsNotNull(stringFunctionExpression.Arguments);
Assert.IsTrue(stringFunctionExpression.Arguments.Length > 0);
}
private void ValidateStringFunctionExpression(DbStringFunctionExpression stringFunctionExpression, DbStringFunctionExpressionType stringFunctionExpressionType)
{
Assert.IsTrue(stringFunctionExpression.ExpressionType == DbExpressionType.Function);
Assert.IsTrue(stringFunctionExpression.StringFunctionExpressionType == stringFunctionExpressionType);
Assert.IsNotNull(stringFunctionExpression.Arguments);
Assert.IsTrue(stringFunctionExpression.Arguments.Length > 0);
}
/// <summary>
/// Initializes a new instance of the <see cref="DbStringFunctionExpression"/> class.
/// </summary>
/// <param name="stringFunctionExpressionType">The <see cref="DbStringFunctionExpressionType"/> of the <see cref="DbStringFunctionExpression"/>.</param>
/// <param name="arguments">The arguments used when calling the function.</param>
internal DbStringFunctionExpression(DbStringFunctionExpressionType stringFunctionExpressionType, DbExpression[] arguments)
: base(DbFunctionExpressionType.String, arguments)
{
StringFunctionExpressionType = stringFunctionExpressionType;
}
/// <summary>
/// Returns the name of the function as it is defined in the target DBMS.
/// </summary>
/// <param name="stringFunctionExpressionType">The <see cref="DbStringFunctionExpressionType"/> that specifies the function name to return.</param>
/// <returns><see cref="string"/></returns>
protected virtual string GetStringFunctionBody(DbStringFunctionExpressionType stringFunctionExpressionType)
{
switch (stringFunctionExpressionType)
{
case DbStringFunctionExpressionType.Length:
return "LENGTH({0})";
case DbStringFunctionExpressionType.Replace:
return "REPLACE({0})";
case DbStringFunctionExpressionType.Reverse:
return "REVERSE({0})";
case DbStringFunctionExpressionType.ToLower:
return "LOWER({0})";
case DbStringFunctionExpressionType.ToUpper:
return "UPPER({0})";
case DbStringFunctionExpressionType.Trim:
return "TRIM({0})";
case DbStringFunctionExpressionType.TrimStart:
return "LTRIM({0})";
case DbStringFunctionExpressionType.TrimEnd:
return "RTRIM({0})";
case DbStringFunctionExpressionType.SoundEx:
return "SOUNDEX({0})";
case DbStringFunctionExpressionType.SubString:
return "SUBSTR({0})";
default:
throw new ArgumentOutOfRangeException("stringFunctionExpressionType", stringFunctionExpressionType, " is not supported");
}
}
/// <summary>
/// Creates a new <see cref="DbStringFunctionExpression"/>.
/// </summary>
/// <param name="stringFunctionExpressionType">The <see cref="DbStringFunctionExpressionType"/> that specifies the type of <see cref="DbStringFunctionExpression"/> to create.</param>
/// <param name="arguments">A list of <see cref="DbExpression"/> instances that is used as arguments when calling the function.</param>
/// <returns>A <see cref="DbStringFunctionExpression"/> instance.</returns>
public DbStringFunctionExpression MakeStringFunction(DbStringFunctionExpressionType stringFunctionExpressionType, DbExpression[] arguments)
{
var stringFunctionExpression = new DbStringFunctionExpression(stringFunctionExpressionType, arguments);
return stringFunctionExpression;
}
