This article is part of our on-going bash tutorial series.
This explains both of the bash for loop methods, and provides 12 different examples on how to use the bash for loop in your shell scripts. Bookmark this article for future reference, as this is the only article you would ever need to refer on how to use bash for loops with examples. In this form, the for statement executes the commands enclosed in a body, once for each item in the list. For example, if the list of values contains 5 items, the for loop will be executed a total of 5 times, once for each item in the list.
The comma will be treated as part of the value. Caution: The list of values should not be enclosed in a double quote. If you enclose in double quote, it will be treated as a single value instead of 5 different valuesas shown in the example below. Caution : As a best practice, you should always quote the bash variables when you are referring it. There are few exceptions to this best practice rule. This is one of them. If you double quote the variable in this for loop, the list of values will be treated as single value.
Lot of people fall into this trap. Be careful and do not double quote your variable in the for loop. Caution: Please be careful if you use this method. It will not go inside the loop. Note : Refer to our earlier article to understand more about bash positional parameters. For example, the following will display all the files and directories under your home directory. This is the concept that is used in the above for5.
The same argument that is used in the ls command above, can be used in a bash for loop, as shown in the example below. Under certain conditions, you can ignore the rest of the commands in the for loop, and continue the loop from the top again for the next value in the listusing the continue command as shown below. This example uses the 2nd method of bash for loop, which is similar to the C for loop syntax. The following example generates 5 random number using the bash C-style for loop.
You need to press Ctrl-C to stop the loop. In the bash c-style loop, apart from increment the value that is used in the condition, you can also increment some other value as shown below. In the initialize section, and the increment section of the bash C-style for loop, you can have multiple value by separating with comma as shown below. The following for loop is executed a total of 5 times, using the variable i. However the variable j start with 5, and getting increment by 5 every time the loop gets executed.
Correction to my earlier post. The alternate infinite for loop using the : nop operator must be while, not for.The For statement specifies the counter variable iand its start and end values.
The Next statement increases the counter variable i by one. With the Step keyword, you can increase or decrease the counter variable by the value you specify. To decrease the counter variable, you must use a negative Step value. You must specify an end value that is less than the start value.
A For Each Next loop repeats a block of code for each item in a collection, or for each element of an array. The Do The code inside this loop will be executed at least one time, even if i is less than The code inside this loop will be executed as long as i is different from 10, and as long as i is greater than Looping through headers How to loop through the six headings in html. While loop How to make a simple Do While loop. If you want to report an error, or if you want to make a suggestion, do not hesitate to send us an e-mail:.
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We will create an array of objects. Learn more. Loop through xml elements Ask Question. Asked 7 years, 4 months ago. Active 7 years ago. Viewed 70k times. Then check for an attribute of SID on the element. I know I am way off but hope you can help. Could you add some more detail? Such as, do you know what the xml will look like?
Active Oldest Votes. Keith Hill Keith Hill k 32 32 gold badges silver badges bronze badges.XML Commands : How to Get data from the XML (Part - 1) - Automation Anywhere - Get Single Node - XML
I assume you'd want to add a statement that checks if sid is null before creating multiple new obj empty objects, so you get an array of objs that are relevant.
InnerXml the Xml content of the child node. Brandon Hawbaker Brandon Hawbaker 5 5 silver badges 4 4 bronze badges.
Sign up or log in Sign up using Google. Sign up using Facebook. Sign up using Email and Password. Post as a guest Name. Email Required, but never shown. The Overflow Blog. Socializing with co-workers while social distancing. Podcast Programming tutorials can be a real drag.Here is an simple Ant example which read a text files and print it to the Ant build output.
Try it out. Thanks for the post. Like Like. Thanks for the prompt response. I now have a slightly different requirement. It says i have 4 different text files each with say 3 lines each line is a one word string for all files. Now i need a foreach loop in ant that reads all 4 files at same time for the first line in each file and stores the values accordingly as 4 different properties. This way for every single iteration of loop i can refer to a target where i can pass these properties for target execution.
The loop will hence run 3 times and execute that target 3 times one for each iteration. Once again thanks for the prompt response. Let say i have 3 text files each with 3 lines and each line is a single word number of lines in the files could be anything but same for all files, so all files will have same number of lines.
Let first file has below 3 lines:- stub1 stub2 stub3.
Foreach Loop Editor (Collection Page)
Second file has:- ver1 ver2 ver3 Third one has:- comp1 comp2 comp3. Now i would like an ant loop or something that can pick first line from each file and pas them as parameter to my destination target as part of first iteration. Then second line from each for second iteration and so on. My Sample code is Many thanks Ykyuen for such great solution. It works perfectly. Only one thing i would like to implement here is that for each file the number of lines will be same but not fixed necessarily 3 here so how can we modify here so that it only picks the number of lines as they are in the files sometimes could be 3 sometimes 2 sometimes 4,etc.
I am already very thankful for the great solutions you have provided so far. I would very much appreciate if i can somehow manage to get this last step implemented. So really looking forward to your response on this and very much appreciate that as always. Perfect that works like a charm: Many thanks for such great solutions so far. Really appreciate it:. What I am trying here is, I am installing 3 WildFly instances using a build.
Currently I am executing a powershell module from buld. Each time it would take the value of each variable which are already mentioned in the properties file. You are commenting using your WordPress.
Apache Ant – for loop example for reading a text file
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Learn how your comment data is processed.Use the Collection pageof the Foreach Loop Editor dialog box to specify the enumerator type and configure the enumerator. Enumerator Select the enumerator type from the list. This property has the options listed in the following table. Expressions Click or expand Expressions to view the list of existing property expressions.
Click the ellipsis button You use the Foreach File enumerator to enumerate files in a folder. The enumerator can be configured to include subfolders. The content of the folders and subfolders that the Foreach File enumerator enumerates might change while the loop is executing because external processes or tasks in the loop add, rename, or delete files while the loop is executing.
This means that a number of unexpected situations may occur:. If files are deleted, one task in the Foreach Loop may perform work on a different set of files than the files used by subsequent tasks. If files are renamed and an external process automatically adds files to replace the renamed files, the Foreach Loop might perform work twice on the same file content. If files are added, it may be difficult to determine for which files the Foreach Loop performed work.
When you specify a file name extension, the enumerator also returns files that have the same extension with additional characters appended. This is the same behavior as that of the dir command in the operating system, which also compares 8.
This behavior of the enumerator could cause unexpected results. However, the enumerator will also return Excel files because those files have the extension, ". You can use an expression to specify the files to include in a collection, by expanding Expressions on the Collection page, selecting the FileSpec property, and then clicking the ellipsis button Fully qualified Select to retrieve the fully qualified path of file names. If wildcard characters are specified in the Files option, then the fully-qualified paths that are returned match the filter.
Name only Select to retrieve only the file names. If wildcard characters are specified in the Files option, then the file names returned match the filter.
Name and extension Select to retrieve the file names and their file name extensions. If wildcard characters are specified in the Files option, then the name and extension of files returned match the filter. You use the Foreach Item enumerator to enumerate items in a collection.
You define the items in the collection by specifying columns and column values. The columns in a row define an item. For example, an item that specifies the executables that an Execute Process task runs and the working directory that the task uses has two columns, one that lists the names of executables and one that lists the working directory. The number of rows determines the number of times that the loop is repeated. If the table has 10 rows, the loop repeats 10 times.The XML Loop allows to get the information about nodes of the document in a loop.
When of every cycle iteration it is possible to save various parameters of the node and the node itself into variables.
Read XML from file. This option is recommended if XML contain encoded strings. When the action reads it from file it decodes all encoded strings automatically. The most popular UTF-8 encoding. XML file should have corresponding header. For example:. Specify the XML text which you want to analyze. The text can be specified explicitly or with using of variables. It is possible to use mask symbols:. The fact of the matter is that sometimes you cannot know a node name beforehand.
For example, this is possible when you select nodes according a mask:. To save the depth of enclosure of the node, switch on this checkbox and enter the variable name. A node depth is a number, 0 corresponds to a root element.
On this tab one can specify the attributes which values are necessary to be saved into variables. It is necessary to specify parameters for every attribute:.
Related Topics. XML Create Node. XML Add Childnode. XML Save. Macro Recorder Settings. Pack Files Extract Files. Evaluate Basic script. Scheduler How to enable wake timer. Quick Start Guide. Getting Started in the RoboTask Window. Create Tasks. Run Tasks. Edit Tasks. Customize RoboTask.
The dark mode beta is finally here. Change your preferences any time. Stack Overflow for Teams is a private, secure spot for you and your coworkers to find and share information. For loop is not officially supported yet by SQL server. Already there is answer on achieving FOR Loop's different ways. I am detailing answer on ways to achieve different types of loops in SQL server.
If you know, you need to complete first iteration of loop anyway, then you can try DO. Learn more. Asked 8 years, 11 months ago. Active 2 months ago. Viewed k times. What is the syntax of a for loop in TSQL?
Somnath Muluk Macho Macho 2, 3 3 gold badges 12 12 silver badges 6 6 bronze badges. SQL is a very different language compared to what you're used to. It's focused on whatnot how. You tell SQL Server what results you want, and let it figure out how to produce the answer. Or, to repharse what I've just said - there isn't a for loop in SQL.
However, this should not be used for most query processing but is sometimes required for imperative manipulation. Avoid loops in favour of JOINs and set operations. If you are not expert in SQL, you should not be considering using a loop. There are only a few conditions where one is needed and most of the rest of the time, using a loop is the equivalent of pushing your car instead of driving it.
Learn to think in terms of data sets instead of looping through records. LOoping is an expert level function not because the syntax is hard but because you need to know exactly how much harm you can do with it before you should be allowed to use it. Sometimes it could be used to quickly conjure up test data in a test database that you're just going to delete soon thereafter anyway. In that case, using this removes the need to go through a separate program written in something more like Cand engineering is not particularly a major concern.
Again, I'm just saying this in terms of test data.