Implementing Syncfusion Blazor Query Builder

The Syncfusion Blazor Query Builder component enables you to build dynamic, customizable query interfaces for filtering data with complex conditions, nested groups, and rule-based logic. It's ideal for advanced search UIs, business rule engines, and data filtering workflows.

Component Overview

The Query Builder organizes filtering logic into:

• Rules: Individual conditions (field = value)
• Groups: Collections of rules combined with AND/OR logic
• Operators: Comparison types (equal, contains, between, etc.)
• Columns: Data source fields that can be filtered

Key capabilities include programmatic rule/group management, event handling, drag-drop UI, state persistence, and extensive customization options.

Navigation Guide

Getting Started

📄 Read: references/getting-started.md

• Installation & setup for Blazor WebAssembly and Blazor Server
• NuGet package configuration
• Initial project setup
• Running your first Query Builder

Basic Setup & Configuration

📄 Read: references/basic-setup.md

• Creating the Query Builder component
• Defining columns and data types
• Configuring button visibility
• Setting default rules and initial state

Filtering, Rules & Groups (Core Feature)

📄 Read: references/filtering-and-rules.md

• Adding and deleting rules programmatically
• Creating and managing groups
• Operators and conditions
• Complex nested group patterns
• User interaction and validation

Data Binding & Filtered Results

📄 Read: references/data-binding.md

• Binding data sources to Query Builder
• Extracting and working with filtered records
• Dynamic data loading patterns
• Applying queries to datasets

Events & Callbacks (Core Feature)

📄 Read: references/events-and-callbacks.md

• Component lifecycle events (Created, Destroyed)
• Rule change tracking (RuleChanged, Changed)
• Pre-change validation (OnValueChange)
• Event-driven query updates

Customization & Styling

📄 Read: references/customization-and-styling.md

• CSS customization and theming
• Template support for custom UI
• Custom operator definitions
• Visual styling of groups and rules

Advanced Features

📄 Read: references/advanced-features.md

• Import/export queries (JSON, URL parameters)
• State persistence and local storage
• Drag-drop rule and group management
• Lock/clone group rules
• Read-only modes
• Query sorting and filtering

Localization & Accessibility

📄 Read: references/localization-and-accessibility.md

• Multi-language support (localization)
• Right-to-Left (RTL) support
• Accessibility best practices
• Keyboard navigation
• Screen reader support

Troubleshooting

📄 Read: references/troubleshooting.md

• Common configuration issues
• Event handling problems
• Data binding troubleshooting
• Performance optimization
• Testing strategies

Quick Start

Here's a minimal example to get started:

@using Syncfusion.Blazor.QueryBuilder

<SfQueryBuilder TValue="Order" DataSource="@Orders">
    <QueryBuilderColumns>
        <QueryBuilderColumn Field="OrderID" Label="Order ID" Type="ColumnType.Number"></QueryBuilderColumn>
        <QueryBuilderColumn Field="CustomerName" Label="Customer" Type="ColumnType.String"></QueryBuilderColumn>
        <QueryBuilderColumn Field="OrderDate" Label="Date" Type="ColumnType.Date"></QueryBuilderColumn>
    </QueryBuilderColumns>
</SfQueryBuilder>

@code {
    private List<Order> Orders { get; set; } = new()
    {
        new() { OrderID = 1, CustomerName = "Acme Corp", OrderDate = new(2024, 1, 15) },
        new() { OrderID = 2, CustomerName = "Tech Ltd", OrderDate = new(2024, 2, 20) }
    };

    public class Order {
        public int OrderID { get; set; }
        public string CustomerName { get; set; }
        public DateTime OrderDate { get; set; }
    }
}

Common Patterns

Add a Rule Programmatically

<SfButton OnClick="AddFilterRule">Add Rule</SfButton>

@code {
    private SfQueryBuilder<Order> QueryBuilder;
    
    private async Task AddFilterRule() {
        var rule = new RuleModel {
            Label = "Order ID",
            Field = "OrderID",
            Type = "Number",
            Operator = "equal",
            Value = 1000
        };
        await QueryBuilder.AddRule(rule, "group0");
    }
}

Capture Query Changes

<SfQueryBuilder TValue="Order" DataSource="@Orders">
    <QueryBuilderEvents TValue="Order" RuleChanged="OnRuleChanged"></QueryBuilderEvents>
</SfQueryBuilder>

@code {
    private void OnRuleChanged(RuleChangeEventArgs args) {
        Console.WriteLine($"Query changed: {args.RuleID}");
        // Apply new filter or update results
    }
}

Export Query to JSON

<SfButton OnClick="ExportQuery">Export</SfButton>

@code {
    private SfQueryBuilder<Order> QueryBuilder;
    
    private async Task ExportQuery() {
        var queryJson = QueryBuilder.GetRules();
        // Save or transmit queryJson
    }
}

Clone a Rule or Group

<SfQueryBuilder TValue="Order" @ref="QueryBuilder">
    <QueryBuilderShowButtons CloneGroup="true" CloneRule="true"></QueryBuilderShowButtons>
</SfQueryBuilder>

<SfButton OnClick="CloneRule">Clone Rule</SfButton>
<SfButton OnClick="CloneGroup">Clone Group</SfButton>

@code {
    private SfQueryBuilder<Order> QueryBuilder;
    
    private void CloneRule() {
        // Clone the first rule at position 1
        QueryBuilder.CloneRule("group0_rule0", 1);
    }
    
    private void CloneGroup() {
        // Clone group1 at position 2
        QueryBuilder.CloneGroup("group1", 2);
    }
}

Lock a Rule or Group

<SfQueryBuilder TValue="Order" @ref="QueryBuilder">
    <QueryBuilderShowButtons LockGroup="true" LockRule="true"></QueryBuilderShowButtons>
</SfQueryBuilder>

<SfButton OnClick="LockRule">Lock Rule</SfButton>
<SfButton OnClick="UnlockRule">Unlock Rule</SfButton>

@code {
    private SfQueryBuilder<Order> QueryBuilder;
    
    private void LockRule() {
        // Lock the rule to prevent editing
        QueryBuilder.LockRule("group0_rule0", true);
    }
    
    private void UnlockRule() {
        // Unlock the rule to allow editing
        QueryBuilder.LockRule("group0_rule0", false);
    }
}

Query Export Methods

The Query Builder provides built-in methods to export queries in different formats:

1. GetSqlFromRules - Export as Inline SQL

Convert query rules to standard SQL WHERE clause format:

<SfQueryBuilder TValue="Order" @ref="QueryBuilder">
    <QueryBuilderColumns>
        <QueryBuilderColumn Field="OrderID" Label="Order ID" Type="ColumnType.Number"></QueryBuilderColumn>
        <QueryBuilderColumn Field="CustomerName" Label="Customer" Type="ColumnType.String"></QueryBuilderColumn>
    </QueryBuilderColumns>
</SfQueryBuilder>

<SfButton OnClick="ExportInlineSQL">Get SQL Query</SfButton>
<p>@SqlQuery</p>

@code {
    private SfQueryBuilder<Order> QueryBuilder;
    private string SqlQuery = "";
    
    private void ExportInlineSQL() {
        RuleModel rules = QueryBuilder.GetValidRules();
        SqlQuery = QueryBuilder.GetSqlFromRules(rules);
        // Output: "OrderID = 1000 AND CustomerName LIKE '%Acme%'"
    }
    
    public class Order {
        public int OrderID { get; set; }
        public string CustomerName { get; set; }
    }
}

2. GetParameterSql - Export as Parameterized SQL

Export SQL with indexed parameters to prevent SQL injection:

@using System.Text.Json

<SfButton OnClick="ExportParameterSQL">Get Parameterized SQL</SfButton>
<pre>@ParameterSqlJson</pre>

@code {
    private SfQueryBuilder<Order> QueryBuilder;
    private string ParameterSqlJson = "";
    
    private void ExportParameterSQL() {
        RuleModel rules = QueryBuilder.GetValidRules();
        ParameterSql paramSql = QueryBuilder.GetParameterSql(rules);
        
        ParameterSqlJson = JsonSerializer.Serialize(paramSql, new JsonSerializerOptions { 
            WriteIndented = true,
            Encoder = System.Text.Encodings.Web.JavaScriptEncoder.UnsafeRelaxedJsonEscaping 
        });
        
        // Access individual properties:
        // paramSql.Sql - SQL string with ? placeholders
        // paramSql.Parameters - List of parameter values
    }
}

Output Example:

{
  "Sql": "OrderID = ? AND CustomerName LIKE ?",
  "Parameters": [1000, "%Acme%"]
}

3. GetNamedParameterSql - Export as Named Parameter SQL

Export SQL with named parameters (@param0, @param1, etc.):

@using System.Text.Json

<SfButton OnClick="ExportNamedParameterSQL">Get Named Parameter SQL</SfButton>
<pre>@NamedParameterSqlJson</pre>

@code {
    private SfQueryBuilder<Order> QueryBuilder;
    private string NamedParameterSqlJson = "";
    
    private void ExportNamedParameterSQL() {
        RuleModel rules = QueryBuilder.GetValidRules();
        NamedParameterSql namedParamSql = QueryBuilder.GetNamedParameterSql(rules);
        
        NamedParameterSqlJson = JsonSerializer.Serialize(namedParamSql, new JsonSerializerOptions { 
            WriteIndented = true,
            Encoder = System.Text.Encodings.Web.JavaScriptEncoder.UnsafeRelaxedJsonEscaping 
        });
        
        // Access individual properties:
        // namedParamSql.Sql - SQL string with @param placeholders
        // namedParamSql.Parameters - Dictionary of parameter names/values
    }
}

Output Example:

{
  "Sql": "OrderID = @param0 AND CustomerName LIKE @param1",
  "Parameters": {
    "@param0": 1000,
    "@param1": "%Acme%"
  }
}

4. GetMongoQuery - Export as MongoDB Query

Convert query rules to MongoDB query format:

@using System.Text.Json

<SfButton OnClick="ExportMongoQuery">Get MongoDB Query</SfButton>
<pre>@MongoQueryJson</pre>

@code {
    private SfQueryBuilder<Order> QueryBuilder;
    private string MongoQueryJson = "";
    
    private void ExportMongoQuery() {
        RuleModel rules = QueryBuilder.GetValidRules();
        string mongoQuery = QueryBuilder.GetMongoQuery(rules);
        
        // Pretty print the JSON
        JsonDocument jsonDoc = JsonDocument.Parse(mongoQuery);
        MongoQueryJson = JsonSerializer.Serialize(jsonDoc.RootElement, new JsonSerializerOptions {
            WriteIndented = true
        });
    }
}

Output Example:

{
  "$and": [
    { "OrderID": { "$eq": 1000 } },
    { "CustomerName": { "$regex": "Acme", "$options": "i" } }
  ]
}

Import Query Methods

You can also import queries back into the Query Builder:

@code {
    // Import from SQL
    private void ImportSQL(string sqlQuery) {
        QueryBuilder.SetRulesFromSql(sqlQuery);
    }
    
    // Import from Parameterized SQL
    private void ImportParameterSQL(ParameterSql paramSql) {
        QueryBuilder.SetParameterSql(paramSql);
    }
    
    // Import from Named Parameter SQL
    private void ImportNamedParameterSQL(NamedParameterSql namedParamSql) {
        QueryBuilder.SetNamedParameterSql(namedParamSql);
    }
    
    // Import from MongoDB Query
    private void ImportMongoQuery(string mongoQuery) {
        QueryBuilder.SetMongoQuery(mongoQuery);
    }
}

Complete Query Export/Import Example

@page "/query-export-demo"
@using Syncfusion.Blazor.QueryBuilder
@using Syncfusion.Blazor.Buttons
@using System.Text.Json

<SfQueryBuilder TValue="Order" @ref="QueryBuilder">
    <QueryBuilderColumns>
        <QueryBuilderColumn Field="OrderID" Label="Order ID" Type="ColumnType.Number"></QueryBuilderColumn>
        <QueryBuilderColumn Field="CustomerName" Label="Customer" Type="ColumnType.String"></QueryBuilderColumn>
        <QueryBuilderColumn Field="OrderDate" Label="Order Date" Type="ColumnType.Date"></QueryBuilderColumn>
        <QueryBuilderColumn Field="Amount" Label="Amount" Type="ColumnType.Number"></QueryBuilderColumn>
    </QueryBuilderColumns>
</SfQueryBuilder>

<div class="button-group">
    <SfButton OnClick="@(() => ExportQuery("SQL"))">Export SQL</SfButton>
    <SfButton OnClick="@(() => ExportQuery("ParameterSQL"))">Export Parameter SQL</SfButton>
    <SfButton OnClick="@(() => ExportQuery("NamedSQL"))">Export Named SQL</SfButton>
    <SfButton OnClick="@(() => ExportQuery("MongoDB"))">Export MongoDB</SfButton>
</div>

<div class="output">
    <h3>@OutputTitle</h3>
    <pre>@OutputQuery</pre>
</div>

@code {
    private SfQueryBuilder<Order> QueryBuilder;
    private string OutputQuery = "";
    private string OutputTitle = "";
    
    private void ExportQuery(string format) {
        RuleModel rules = QueryBuilder.GetValidRules();
        
        switch(format) {
            case "SQL":
                OutputTitle = "Inline SQL Query";
                OutputQuery = QueryBuilder.GetSqlFromRules(rules);
                break;
                
            case "ParameterSQL":
                OutputTitle = "Parameterized SQL Query";
                ParameterSql paramSql = QueryBuilder.GetParameterSql(rules);
                OutputQuery = JsonSerializer.Serialize(paramSql, new JsonSerializerOptions { 
                    WriteIndented = true,
                    Encoder = System.Text.Encodings.Web.JavaScriptEncoder.UnsafeRelaxedJsonEscaping 
                });
                break;
                
            case "NamedSQL":
                OutputTitle = "Named Parameter SQL Query";
                NamedParameterSql namedSql = QueryBuilder.GetNamedParameterSql(rules);
                OutputQuery = JsonSerializer.Serialize(namedSql, new JsonSerializerOptions { 
                    WriteIndented = true,
                    Encoder = System.Text.Encodings.Web.JavaScriptEncoder.UnsafeRelaxedJsonEscaping 
                });
                break;
                
            case "MongoDB":
                OutputTitle = "MongoDB Query";
                string mongoQuery = QueryBuilder.GetMongoQuery(rules);
                JsonDocument jsonDoc = JsonDocument.Parse(mongoQuery);
                OutputQuery = JsonSerializer.Serialize(jsonDoc.RootElement, new JsonSerializerOptions {
                    WriteIndented = true
                });
                break;
        }
    }
    
    public class Order {
        public int OrderID { get; set; }
        public string CustomerName { get; set; }
        public DateTime OrderDate { get; set; }
        public decimal Amount { get; set; }
    }
}

Key Features at a Glance

Next Steps

1. Start with references/getting-started.md to set up your environment
2. Follow references/basic-setup.md for component configuration
3. Explore references/filtering-and-rules.md for core filtering logic
4. Handle queries with references/events-and-callbacks.md
5. Refer to other guides as needed for advanced scenarios