ruby and watir学习之_Array 类
Array 类说明
函数名称 |
说明 |
示例 |
& |
数组与,返回两数组的交集 |
[1,2] & [2,3] » [2] |
* |
复制数组 n 次 |
[1,2]*2 » [1,2,1,2] |
+ |
返回两数组的并集,但不排除重复元素 |
[1,2]+[2,3] » [1,2,2,3] |
<< |
追加元素,但不排除重复元素 |
[1,2]<<[2,3] » [1,2,2,3] |
| |
追加元素,但排除重复元素 |
1,2] | [2,3] » [1,2,3] |
- |
返回第一个数组与第二个数组不同的元 素 |
[1,2]-[2,3] » [1] |
<=> |
比较数组 |
[1,2]<=>[2,3] »flase |
== |
比较数组,若所有元素均相等时返回真 |
[1,2]==[2,1] »flase |
assoc |
从数组的每个元素中寻找指定对象 |
[[1,2],[3,4]].assoc(2) » [1,2] |
at |
找到数组的第 N 个元素 负数表示逆向查找 |
["a","b","c","d","e"].at(0) » "a" ["a","b","c","d","e"].at(-1) » "e" |
clear |
删除数组中的所有元素 |
["a","b","c","d","e"]. clear |
collect collect! |
用一个过程块对数组的每个元素进行处 理 |
["a","b","c","d"].collect {|x| x + "!" } » ["a!", "b!", "c!", "d!"] |
compact compact! |
删除值为 nil 的元素后生成新数组并返 回它 |
["a",nil,"b",nil,"c",nil].compact » ["a", "b", "c"] |
delete |
删除元素,如果元素重复,全部删除 |
a = [ "a", "b", "b", "b", "c" ] a.delete("b") puts a » ["a","c"] |
delete_at |
删除 pos 所指位置的元素并返回它。若 pos 超出数组范围则返回 nil |
a = %w( ant bat cat dog ) a.delete_at(2) » "cat" a » ["ant", "bat", "dog"] a.delete_at(99) » nil |
delete_if |
根据条件删除 |
a = [ "a", "b", "c" ] a.delete_if {|x| x >= "b" } » ["a"] |
each |
对数组的每个元素按值进行迭代操作 |
a = [ "a", "b", "c" ] a.each {|x| print x, " -- " } » "a -- b -- c --" |
each_index |
对数组的每个元素按索引进行迭代操作 |
a = [ "a", "b", "c" ] a.each_index {|x| print x, " -- " } » "0 -- 1 -- 2 --" |
empty? |
判断数组是否为空,为空则返回真 |
[].empty? » true |
eql! |
比较两数组是否相等 |
["a","b","c"].eql?(["a","b","c"]) » true |
fill |
填充数组 |
["a","b","c","d"].fill("x") » ["x","x","x","x"] ["a","b","c","d"].fill("z", 2, 2) » ["x", "x", "z", "z"] |
first |
返回数组的首元素。若没有首元素则返 回 nil |
[ "q", "r", "s", "t" ].first » "q" |
last |
返回数组末尾的元素。若数组为空时, 返回 nil |
["w","x","y","z"].last » "z" |
include? |
判断数组中是否包含元素 |
a = [ "a", "b", "c" ] a.include?("b") » true a.include?("z") » false |
index |
返回数组中第一个==val 的元素的位置 |
a = [ "a", "b", "c" ] a.index("b") » 1 a.index("z") » nil |
indexes |
以数组形式返回其索引值与各参数值相 等的元素 |
a = [ "a", "b", "c", "d", "e", "f", "g" ] a.indexes(0, 2, 4) » ["a", "c", "e"] a.indexes( 2, 4, 12) » [ "c", "e", nil] |
insert |
在索引为 nth 的元素前面插入第 2 参数 以后的值 |
ary = %w(foo bar baz) ary.insert 2,'a','b' p ary » ["foo", "bar", "a", "b", "baz"] |
join |
将数组元素按一定的分隔符连接起来 |
[ "a", "b", "c" ].join » "abc" [ "a", "b", "c" ].join("-") » "a-b-c" |
length size |
返回数组长度。若数组为空则返回 0 |
[1,2,3].length » 3 [1,2,3].size » 3 |
nitems |
返回非 nil 元素的个数 |
[ 1, nil, 3, nil, 5 ].nitems » 3 |
pop |
删除末尾元素并返回它。若数组为空则 返回 nil |
a = [ "a", "m", "z" ] a.pop » "z" p a » ["a", "m"] |
push |
添加新元素 |
["a","b"].push(['1','2']) » ["a", "b", ["1", "2"]] |
rassoc |
遍历数组每个元素(元素必须是数组), 匹配索引为 1 的值是否与查找的字符相 等,返回第一个相等的元素 |
a = [[15,1], [25,2], [35,2]] p a.rassoc(2) » [25, 2] |
replace |
替换数组元素 |
a = ["a","b"] a.replace(["x","y","z"]) p a »["x", "y", "z"] |
reverse reverse! |
将所有元素以逆序重新排列生成新数组 并返回它 |
["a","b","c" ].reverse » ["c", "b", "a"] |
rindex |
返回最后一个值相等的元素的索引值 |
a = [ "a","b","b","b","c"] a.rindex("b") » 3 |
shift |
删除数组的首元素并返回它。剩余元素 依次提前。若数组为空返回 nil。 |
args = ["-m","-q","filename"] args.shift » "-m" args » ["-q", "filename"] |
sort sort! |
从小到大排序 |
a = [ "d", "a", "e", "c", "b" ] a.sort » ["a", "b", "c", "d", "e"] |
uniq uniq! |
删除数组中的重复元素后生成新数组并 返回它 |
a = [ "a", "a", "b", "b", "c" ] a.uniq » ["a", "b", "c"] |
unshift |
在数组第一个元素前添加元素 |
a = [ "b", "c", "d" ] a.unshift("a") » ["a", "b", "c", "d"] |
to_s |
将数组的所有元素连接成字符串 |
["a","e","i","o"].to_s » "aeio" |
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