查询词典 null hypothesis

The binary + operator performs string concatenation when one or both operands are of type string. If an operand of string concatenation is null, an empty string is substituted. Otherwise, any non-string argument is converted to its string representation by invoking the virtual ToString method inherited from type object.

由此可知 C#的加号运算子预设就支援字串串加的功能，只要一群字串串接的物件中只要有一个以上的物件型别是「字串」的话，就会全部变成「字串相加」，只要遇到「非字串」的物件，预设会使用继承至 object 物件的 ToString 方法进行转型，让所有物件都变成「字串」后进行相加动作。

Concha F%Barrientos A%Munoz L A phenomenological model of a hydrocyclone London , 1996,null

刘晓敏%蒋明虎脱油型水力旋流器空气核的稳定性分析石油学报， 2004，6

Santa Regina I%Leonardi S%Rapp M Foliar nutrient dynamics and nutrient-use efficiency in Castanea sativa coppice stands of southern Europe 10.1093/forestry/74.1.1 Forestry , 2001,null

徐福余%王力华%李培芝%许思明%张颂云若干北方落叶树木叶片养分的内外迁移：Ⅰ。浓度和含量的变化应用生态学报， 1997，1

Cowper G R%Symonds P S Strain Hardening and Strain-rate Effects in the Impact Loading of Cantilever Beams Brown Univ Division of Applied Mathematics Report No.28 , 1957,null

封加波 对薄层柱壳爆炸膨胀断裂过程的研究高压物理学报， 1988，(2)章冠人韧性和脆性断裂的分形维数爆炸与冲击， 1996，2

Chen Weimin%Guo Xiaoming Annual change in zooplanktonic crustacea and their relationship with physico-chemical factors in Chonghu Lake International Journal of Ecology and Environmental Sciences , 1987,null

陈伟民%秦伯强太湖梅梁湾冬末春初浮游动物时空变化及其环境意义湖泊科学， 1998，(4)黄祥飞湖泊生态调查观测与分析北京：中国标准出版社， 1999，null

Check to ensure that the current value is not null/Nothing.

检查以确保目前的值不为null /没有。

The next parameter should be null unless you want to use a custom software rasterizer, which is very unlikely.

下一个参数应该是空，除非你想使用自定义的软件光栅，这是非常不可能的。

Dawe R O%Oswald T R%Robson I A Oil Recovery Process Using Mobility Control Fluid Comprising Alkylated Diphenyl Oxide Sulfonates and Foam Forming Amphoteric Suffactants US Pat Appl,US5203411 , 1993,null

张玉芬%乔聪震%张金昌%李成岳离子液体合成长链烷基苯 10.3321/j.issn：1000-8144.2003.10.004 石油化工， 2003，(10)彭朴采油用表面活性剂北京：化学工业出版社， 2003，null

Other than the difference with default values for optional arguments, you should assign a default when a passed argument has a null value.

和PHP不同的是可选参数，你需要比较它是否是空的，再赋给它一个默认值。

Fan Delian Metal Enrichment-Layer in Lower Cambrian Black Rock in South China. Study on Sediment and Petrology 北京:科学出版社, 1981,null

范德廉 南方几省下寒武统黑色岩系及层状多金属富集层北京：科学出版社， 1981，null

Foods high in this vitamin include oily fish such as salmon, tuna and, and fish liver oils.

维生素D含量高的食物包括诸如大麻哈鱼、金枪鱼和鲭鱼之类的油鱼以及鱼肝油。

We need you to cosign our public letter demanding that press intimidation cease immediately, and that all charges be dropped.

我们需要您cosign我们的公共信，要求记者立即停止恐吓，并要求所有收费下降。