IsNullOrEmpty(string)和List.Count>髭尖的0

时间:2016-06-28 14:52:54

标签: c# template-engine mustache

我使用mustache-sharp作为模板引擎

我想知道无论如何使用此模板引擎并且有两个条件来检查

1) IsNullOrEmpty(string)  => e.g. {{#IsNullOrEmpty MyName}}} {{/IsNullOrEmpty}}
2) List.Count > 0         => e.g. {{#Any Persons}} {{/Any}}

任何人都可以指导我如何创建上述标签?

1 个答案:

答案 0 :(得分:1)

您可以尝试创建自定义 ContentTagDefinition 并在 HtmlFormatCompiler 中注册。

例如:

  1. <强> IsNullOrEmpty

    public class IsNullOrEmptyTagDefinition : ContentTagDefinition
    {
        private const string conditionParameter = "condition";
    
        public IsNullOrEmptyTagDefinition()
            : base("IsNullOrEmpty")
        {}
    
        public override IEnumerable<TagParameter> GetChildContextParameters()
        {
            return new TagParameter[0];
        }
    
        public override bool ShouldGeneratePrimaryGroup(Dictionary<string, object> arguments)
        {
            object condition = arguments[conditionParameter];
            return isConditionSatisfied(condition);
        }
    
        protected override IEnumerable<TagParameter> GetParameters()
        {
            return new TagParameter[] { new TagParameter(conditionParameter) { IsRequired = true } };
        }
    
        protected override bool GetIsContextSensitive()
        {
            return false;
        }
    
        private bool isConditionSatisfied(object condition)
        {
            if (condition == null)
            {
                return true;
            }
    
            return condition is string ? string.IsNullOrEmpty(condition as string) : false;
        }
    
    }
    
  2. <强>任何

    public class AnyTagDefinition : ContentTagDefinition
    {
        private const string conditionParameter = "condition";
    
        public AnyTagDefinition()
            : base("Any")
        {}
    
        public override IEnumerable<TagParameter> GetChildContextParameters()
        {
            return new TagParameter[0];
        }
    
        public override bool ShouldGeneratePrimaryGroup(Dictionary<string, object> arguments)
        {
            object condition = arguments[conditionParameter];
            return isConditionSatisfied(condition);
        }
    
        protected override IEnumerable<TagParameter> GetParameters()
        {
            return new TagParameter[] { new TagParameter(conditionParameter) { IsRequired = true } };
        }
    
        protected override bool GetIsContextSensitive()
        {
            return false;
        }
    
        private bool isConditionSatisfied(object condition)
        {
            if (condition is IEnumerable)
            {
                return (condition as IEnumerable).Cast<object>().Any();
            }
    
            return false;
        }
    
    }
    
  3. 注册两个标签

    HtmlFormatCompiler compiler = new HtmlFormatCompiler();
    compiler.RegisterTag(new IsNullOrEmptyTagDefinition(), true);
    compiler.RegisterTag(new AnyTagDefinition(), true);