Merge pull request #915 from mikependon/repodb-enhancements

#899 - place all the QueryField objects back into the Core library.

RepoDb.Core/RepoDb/Extensions/QueryFields/FunctionalQueryField.cs

@@ -0,0 +1,177 @@
+using RepoDb.Enumerations;
+using RepoDb.Interfaces;
+using System;
+
+namespace RepoDb.Extensions.QueryFields
+{
+    /// <summary>
+    /// A dynamic functional-based <see cref="QueryField"/> object. This requires a properly constructed
+    /// formatted string (for a specific database function) in order to work properly.
+    /// </summary>
+    /// <example>
+    /// See sample code below that uses a TRIM function.
+    /// <code>
+    ///     var where = new FunctionalQueryField("ColumnName", "Value", "TRIM({0})");
+    ///     var result = connection.Query&lt;Entity&gt;(where);
+    /// </code>
+    /// </example>
+    public class FunctionalQueryField : QueryField, IEquatable<FunctionalQueryField>
+    {
+        private int? hashCode = null;
+
+        #region Constructors
+
+        /// <summary>
+        /// Creates a new instance of <see cref="FunctionalQueryField"/> object.
+        /// </summary>
+        /// <param name="fieldName">The name of the field for the query expression.</param>
+        /// <param name="value">The value to be used for the query expression.</param>
+        /// <param name="format">The properly constructed format of the target function to be used.</param>
+        public FunctionalQueryField(string fieldName,
+            object value,
+            string format)
+            : this(fieldName, Operation.Equal, value, format)
+        { }
+
+        /// <param name="field">The actual field for the query expression.</param>
+        /// <param name="value">The value to be used for the query expression.</param>
+        /// <param name="format">The properly constructed format of the target function to be used.</param>
+        public FunctionalQueryField(Field field,
+            object value,
+            string format)
+            : this(field, Operation.Equal, value, format)
+        { }
+
+        /// <param name="fieldName">The name of the field for the query expression.</param>
+        /// <param name="operation">The operation to be used for the query expression.</param>
+        /// <param name="value">The value to be used for the query expression.</param>
+        /// <param name="format">The properly constructed format of the target function to be used.</param>
+        public FunctionalQueryField(string fieldName,
+            Operation operation,
+            object value,
+            string format)
+            : this(new Field(fieldName), operation, value, format)
+        { }
+
+        /// <param name="field">The actual field for the query expression.</param>
+        /// <param name="operation">The operation to be used for the query expression.</param>
+        /// <param name="value">The value to be used for the query expression.</param>
+        /// <param name="format">The properly constructed format of the target function to be used.</param>
+        public FunctionalQueryField(Field field,
+            Operation operation,
+            object value,
+            string format)
+            : base(field, operation, value)
+        {
+            Format = format;
+        }
+
+        #endregion
+
+        #region Properties
+
+        /// <summary>
+        /// Gets the properly constructed format of the target function.
+        /// </summary>
+        public string Format { get; }
+
+        #endregion
+
+        #region Methods
+
+        /// <summary>
+        /// Gets the string representations (column-value pairs) of the current <see cref="QueryField"/> object with the formatted-function transformations.
+        /// </summary>
+        /// <param name="index">The target index.</param>
+        /// <param name="dbSetting">The database setting currently in used.</param>
+        /// <returns>The string representations of the current <see cref="QueryField"/> object using the LOWER function.</returns>
+        public override string GetString(int index,
+            IDbSetting dbSetting) =>
+            base.GetString(index, Format, dbSetting);
+
+        #endregion
+
+        #region Equality and comparers
+
+        /// <summary>
+        /// Returns the hashcode for this <see cref="FunctionalQueryField"/>.
+        /// </summary>
+        /// <returns>The hashcode value.</returns>
+        public override int GetHashCode()
+        {
+            if (this.hashCode != null)
+            {
+                return this.hashCode.Value;
+            }
+
+            // FullName: This is to ensure that even the user has created an identical formatting 
+            //  on the derived class with the existing classes, the Type.FullName could still 
+            // differentiate the instances
+            var hashCode = GetType().FullName.GetHashCode();
+
+            // Base
+            hashCode += base.GetHashCode();
+
+            // Format
+            if (Format != null)
+            {
+                hashCode += Format.GetHashCode();
+            }
+
+            // Return
+            return (this.hashCode = hashCode).Value;
+        }
+
+        /// <summary>
+        /// Compares the <see cref="FunctionalQueryField"/> object equality against the given target object.
+        /// </summary>
+        /// <param name="obj">The object to be compared to the current object.</param>
+        /// <returns>True if the instances are equals.</returns>
+        public override bool Equals(object obj)
+        {
+            if (obj is null) return false;
+
+            return obj.GetHashCode() == GetHashCode();
+        }
+
+        /// <summary>
+        /// Compares the <see cref="FunctionalQueryField"/> object equality against the given target object.
+        /// </summary>
+        /// <param name="other">The object to be compared to the current object.</param>
+        /// <returns>True if the instances are equal.</returns>
+        public bool Equals(FunctionalQueryField other)
+        {
+            if (other is null) return false;
+
+            return other.GetHashCode() == GetHashCode();
+        }
+
+        /// <summary>
+        /// Compares the equality of the two <see cref="FunctionalQueryField"/> objects.
+        /// </summary>
+        /// <param name="objA">The first <see cref="FunctionalQueryField"/> object.</param>
+        /// <param name="objB">The second <see cref="FunctionalQueryField"/> object.</param>
+        /// <returns>True if the instances are equal.</returns>
+        public static bool operator ==(FunctionalQueryField objA,
+            FunctionalQueryField objB)
+        {
+            if (objA is null)
+            {
+                return objB is null;
+            }
+            return objA.Equals(objB);
+        }
+
+        /// <summary>
+        /// Compares the inequality of the two <see cref="FunctionalQueryField"/> objects.
+        /// </summary>
+        /// <param name="objA">The first <see cref="FunctionalQueryField"/> object.</param>
+        /// <param name="objB">The second <see cref="FunctionalQueryField"/> object.</param>
+        /// <returns>True if the instances are not equal.</returns>
+        public static bool operator !=(FunctionalQueryField objA,
+            FunctionalQueryField objB) =>
+            (objA == objB) == false;
+
+        #endregion
+    }
+}

RepoDb.Core/RepoDb/Extensions/QueryFields/LeftQueryField.cs

@@ -0,0 +1,107 @@
+using RepoDb.Enumerations;
+
+namespace RepoDb.Extensions.QueryFields
+{
+    /// <summary>
+    /// A functional-based <see cref="QueryField"/> object that is using the LEFT function.
+    /// </summary>
+    public sealed class LeftQueryField : FunctionalQueryField
+    {
+        private int? hashCode = null;
+
+        #region Constructors
+
+        /// <summary>
+        /// Creates a new instance of <see cref="LeftQueryField"/> object.
+        /// </summary>
+        /// <param name="fieldName">The name of the field for the query expression.</param>
+        /// <param name="value">The value to be used for the query expression.</param>
+        public LeftQueryField(string fieldName,
+            string value)
+            : this(fieldName, Operation.Equal, value)
+        { }
+
+        /// <summary>
+        /// Creates a new instance of <see cref="LeftQueryField"/> object.
+        /// </summary>
+        /// <param name="field">The actual field for the query expression.</param>
+        /// <param name="value">The value to be used for the query expression.</param>
+        public LeftQueryField(Field field,
+            string value)
+            : this(field, Operation.Equal, value)
+        { }
+
+        /// <summary>
+        /// Creates a new instance of <see cref="LeftQueryField"/> object.
+        /// </summary>
+        /// <param name="fieldName">The name of the field for the query expression.</param>
+        /// <param name="operation">The operation to be used for the query expression.</param>
+        /// <param name="value">The value to be used for the query expression.</param>
+        public LeftQueryField(string fieldName,
+            Operation operation,
+            string value)
+            : this(new Field(fieldName), operation, value)
+        { }
+
+        /// <summary>
+        /// Creates a new instance of <see cref="LeftQueryField"/> object.
+        /// </summary>
+        /// <param name="field">The actual field for the query expression.</param>
+        /// <param name="operation">The operation to be used for the query expression.</param>
+        /// <param name="value">The value to be used for the query expression.</param>
+        public LeftQueryField(Field field,
+            Operation operation,
+            string value)
+            : this(field, operation, value, (value?.Length).GetValueOrDefault())
+        { }
+
+        /// <param name="field">The actual field for the query expression.</param>
+        /// <param name="operation">The operation to be used for the query expression.</param>
+        /// <param name="value">The value to be used for the query expression.</param>
+        /// <param name="charCount">The number of characters from the left to be evaluated.</param>
+        private LeftQueryField(Field field,
+            Operation operation,
+            string value,
+            int charCount)
+            : base(field, operation, value, $"LEFT({{0}}, {charCount})")
+        {
+            CharCount = charCount;
+        }
+
+        #endregion
+
+        #region Properties
+
+        /// <summary>
+        /// Gets the value that defines the number of characters from the left to be evaluated.
+        /// </summary>
+        public int CharCount { get; }
+
+        #endregion
+
+        #region Equality and comparers
+
+        /// <summary>
+        /// Returns the hashcode for this <see cref="LeftQueryField"/>.
+        /// </summary>
+        /// <returns>The hashcode value.</returns>
+        public override int GetHashCode()
+        {
+            if (this.hashCode != null)
+            {
+                return this.hashCode.Value;
+            }
+
+            // Base
+            var hashCode = base.GetHashCode();
+
+            // CharCount
+            hashCode += CharCount.GetHashCode();
+
+            // Return
+            return (this.hashCode = hashCode).Value;
+        }
+
+        #endregion
+    }
+}

RepoDb.Core/RepoDb/Extensions/QueryFields/LeftTrimQueryField.cs

@@ -0,0 +1,49 @@
+using RepoDb.Enumerations;
+
+namespace RepoDb.Extensions.QueryFields
+{
+    /// <summary>
+    /// A functional-based <see cref="QueryField"/> object that is using the LTRIM function.
+    /// </summary>
+    public sealed class LeftTrimQueryField : FunctionalQueryField
+    {
+        #region Constructors
+
+        /// <summary>
+        /// Creates a new instance of <see cref="LeftTrimQueryField"/> object.
+        /// </summary>
+        /// <param name="fieldName">The name of the field for the query expression.</param>
+        /// <param name="value">The value to be used for the query expression.</param>
+        public LeftTrimQueryField(string fieldName,
+            string value)
+            : this(fieldName, Operation.Equal, value)
+        { }
+
+        /// <param name="field">The actual field for the query expression.</param>
+        /// <param name="value">The value to be used for the query expression.</param>
+        public LeftTrimQueryField(Field field,
+            string value)
+            : this(field, Operation.Equal, value)
+        { }
+
+        /// <param name="fieldName">The name of the field for the query expression.</param>
+        /// <param name="operation">The operation to be used for the query expression.</param>
+        /// <param name="value">The value to be used for the query expression.</param>
+        public LeftTrimQueryField(string fieldName,
+            Operation operation,
+            string value)
+            : this(new Field(fieldName), operation, value)
+        { }
+
+        /// <param name="field">The actual field for the query expression.</param>
+        /// <param name="operation">The operation to be used for the query expression.</param>
+        /// <param name="value">The value to be used for the query expression.</param>
+        public LeftTrimQueryField(Field field,
+            Operation operation,
+            string value)
+            : base(field, operation, value, "LTRIM({0})")
+        { }
+
+        #endregion
+    }
+}

RepoDb.Core/RepoDb/Extensions/QueryFields/LenQueryField.cs

@@ -0,0 +1,50 @@
+using RepoDb.Enumerations;
+
+namespace RepoDb.Extensions.QueryFields
+{
+    /// <summary>
+    /// A functional-based <see cref="QueryField"/> object that is using the LEN function.
+    /// This only works on SQL Server database provider.
+    /// </summary>
+    public sealed class LenQueryField : FunctionalQueryField
+    {
+        #region Constructors
+
+        /// <summary>
+        /// Creates a new instance of <see cref="LenQueryField"/> object.
+        /// </summary>
+        /// <param name="fieldName">The name of the field for the query expression.</param>
+        /// <param name="value">The value to be used for the query expression.</param>
+        public LenQueryField(string fieldName,
+            int value)
+            : this(fieldName, Operation.Equal, value)
+        { }
+
+        /// <param name="field">The actual field for the query expression.</param>
+        /// <param name="value">The value to be used for the query expression.</param>
+        public LenQueryField(Field field,
+            int value)
+            : this(field, Operation.Equal, value)
+        { }
+
+        /// <param name="fieldName">The name of the field for the query expression.</param>
+        /// <param name="operation">The operation to be used for the query expression.</param>
+        /// <param name="value">The value to be used for the query expression.</param>
+        public LenQueryField(string fieldName,
+            Operation operation,
+            int value)
+            : this(new Field(fieldName), operation, value)
+        { }
+
+        /// <param name="field">The actual field for the query expression.</param>
+        /// <param name="operation">The operation to be used for the query expression.</param>
+        /// <param name="value">The value to be used for the query expression.</param>
+        public LenQueryField(Field field,
+            Operation operation,
+            int value)
+            : base(field, operation, value, "LEN({0})")
+        { }
+
+        #endregion
+    }
+}